---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '21159'
abstract:
- lang: eng
  text: "One of the foundational theorems of extremal graph theory is Dirac’s theorem,
    which\r\nsays that if an n-vertex graph G has minimum degree at least n/2, then
    G has a\r\nHamilton cycle, and therefore a perfect matching (if n is even). Later
    work by Sárközy,\r\nSelkow and Szemerédi showed that in fact Dirac graphs have
    many Hamilton cycles\r\nand perfect matchings, culminating in a result of Cuckler
    and Kahn that gives a precise\r\ndescription of the numbers of Hamilton cycles
    and perfect matchings in a Dirac graph\r\nG (in terms of an entropy-like parameter
    of G). In this paper we extend Cuckler\r\nand Kahn’s result to perfect matchings
    in hypergraphs. For positive integers d < k,\r\nand for n divisible by k, let
    md (k, n) be the minimum d-degree that ensures the\r\nexistence of a perfect matching
    in an n-vertex k-uniform hypergraph. In general, it is\r\nan open question to
    determine (even asymptotically) the values of md (k, n), but we are\r\nnonetheless
    able to prove an analogue of the Cuckler–Kahn theorem, showing that if\r\nan n-vertex
    k-uniform hypergraph G has minimum d-degree at least (1+γ )md (k, n)\r\n(for any
    constantγ > 0), then the number of perfect matchings in G is controlled by\r\nan
    entropy-like parameter of G. This strengthens cruder estimates arising from work\r\nof
    Kang–Kelly–Kühn–Osthus–Pfenninger and Pham–Sah–Sawhney–Simkin."
acknowledgement: We would like to thank the referees for a number of helpful comments
  and suggestions, which have substantially improved the paper. Open access funding
  provided by Institute of Science and Technology (IST Austria).
article_number: '5'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Matthew Alan
  full_name: Kwan, Matthew Alan
  id: 5fca0887-a1db-11eb-95d1-ca9d5e0453b3
  last_name: Kwan
  orcid: 0000-0002-4003-7567
- first_name: Roodabeh
  full_name: Safavi Hemami, Roodabeh
  id: 72ed2640-8972-11ed-ae7b-f9c81ec75154
  last_name: Safavi Hemami
- first_name: Yiting
  full_name: Wang, Yiting
  id: 1917d194-076e-11ed-97cd-837255f88785
  last_name: Wang
  orcid: 0000-0002-2856-767X
citation:
  ama: Kwan MA, Safavi Hemami R, Wang Y. Counting perfect matchings in Dirac hypergraphs.
    <i>Combinatorica</i>. 2026;46. doi:<a href="https://doi.org/10.1007/s00493-025-00194-8">10.1007/s00493-025-00194-8</a>
  apa: Kwan, M. A., Safavi Hemami, R., &#38; Wang, Y. (2026). Counting perfect matchings
    in Dirac hypergraphs. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-025-00194-8">https://doi.org/10.1007/s00493-025-00194-8</a>
  chicago: Kwan, Matthew Alan, Roodabeh Safavi Hemami, and Yiting Wang. “Counting
    Perfect Matchings in Dirac Hypergraphs.” <i>Combinatorica</i>. Springer Nature,
    2026. <a href="https://doi.org/10.1007/s00493-025-00194-8">https://doi.org/10.1007/s00493-025-00194-8</a>.
  ieee: M. A. Kwan, R. Safavi Hemami, and Y. Wang, “Counting perfect matchings in
    Dirac hypergraphs,” <i>Combinatorica</i>, vol. 46. Springer Nature, 2026.
  ista: Kwan MA, Safavi Hemami R, Wang Y. 2026. Counting perfect matchings in Dirac
    hypergraphs. Combinatorica. 46, 5.
  mla: Kwan, Matthew Alan, et al. “Counting Perfect Matchings in Dirac Hypergraphs.”
    <i>Combinatorica</i>, vol. 46, 5, Springer Nature, 2026, doi:<a href="https://doi.org/10.1007/s00493-025-00194-8">10.1007/s00493-025-00194-8</a>.
  short: M.A. Kwan, R. Safavi Hemami, Y. Wang, Combinatorica 46 (2026).
corr_author: '1'
date_created: 2026-02-08T23:02:49Z
date_published: 2026-02-01T00:00:00Z
date_updated: 2026-02-16T09:55:17Z
day: '01'
ddc:
- '510'
department:
- _id: MaKw
- _id: MoHe
doi: 10.1007/s00493-025-00194-8
external_id:
  arxiv:
  - '2408.09589'
file:
- access_level: open_access
  checksum: 47b0031d90b0e6b9a843f422a1486089
  content_type: application/pdf
  creator: dernst
  date_created: 2026-02-16T09:52:38Z
  date_updated: 2026-02-16T09:52:38Z
  file_id: '21228'
  file_name: 2026_Combinatorica_Kwan.pdf
  file_size: 539646
  relation: main_file
  success: 1
file_date_updated: 2026-02-16T09:52:38Z
has_accepted_license: '1'
intvolume: '        46'
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '02'
oa: 1
oa_version: Published Version
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Counting perfect matchings in Dirac hypergraphs
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 46
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '22159'
abstract:
- lang: eng
  text: 'The size Ramsey number of a graph H is defined as the minimum number of edges
    in a graph G such that there is a monochromatic copy of H in every two-coloring
    of E(G). The size Ramsey number was introduced by Erdős, Faudree, Rousseau, and
    Schelp in 1978 and they ended their foundational paper by asking whether one can
    determine up to a constant factor the size Ramsey numbers of three families of
    graphs: complete bipartite graphs, book graphs (obtained by adding many common
    neighbors to the vertices of a clique), and starburst graphs (obtained by adding
    many pendant edges to each vertex of a clique). In this paper, we completely resolve
    the latter two questions and make substantial progress on the first by determining
    the size Ramsey number of Ks,t up to a constant factor for all t=Ω(s log s).'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: David
  full_name: Conlon, David
  last_name: Conlon
- first_name: Jacob
  full_name: Fox, Jacob
  last_name: Fox
- first_name: Yuval
  full_name: Wigderson, Yuval
  id: 2d0023a0-1567-11f0-833d-d5c1e476d4b5
  last_name: Wigderson
citation:
  ama: Conlon D, Fox J, Wigderson Y. Three early problems on size Ramsey numbers.
    <i>Combinatorica</i>. 2023;43(4):743-768. doi:<a href="https://doi.org/10.1007/s00493-023-00034-7">10.1007/s00493-023-00034-7</a>
  apa: Conlon, D., Fox, J., &#38; Wigderson, Y. (2023). Three early problems on size
    Ramsey numbers. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-023-00034-7">https://doi.org/10.1007/s00493-023-00034-7</a>
  chicago: Conlon, David, Jacob Fox, and Yuval Wigderson. “Three Early Problems on
    Size Ramsey Numbers.” <i>Combinatorica</i>. Springer Nature, 2023. <a href="https://doi.org/10.1007/s00493-023-00034-7">https://doi.org/10.1007/s00493-023-00034-7</a>.
  ieee: D. Conlon, J. Fox, and Y. Wigderson, “Three early problems on size Ramsey
    numbers,” <i>Combinatorica</i>, vol. 43, no. 4. Springer Nature, pp. 743–768,
    2023.
  ista: Conlon D, Fox J, Wigderson Y. 2023. Three early problems on size Ramsey numbers.
    Combinatorica. 43(4), 743–768.
  mla: Conlon, David, et al. “Three Early Problems on Size Ramsey Numbers.” <i>Combinatorica</i>,
    vol. 43, no. 4, Springer Nature, 2023, pp. 743–68, doi:<a href="https://doi.org/10.1007/s00493-023-00034-7">10.1007/s00493-023-00034-7</a>.
  short: D. Conlon, J. Fox, Y. Wigderson, Combinatorica 43 (2023) 743–768.
date_created: 2026-06-29T10:51:32Z
date_published: 2023-08-01T00:00:00Z
date_updated: 2026-07-08T10:34:40Z
day: '01'
doi: 10.1007/s00493-023-00034-7
extern: '1'
external_id:
  arxiv:
  - '2111.05420'
intvolume: '        43'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2111.05420
month: '08'
oa: 1
oa_version: Preprint
page: 743-768
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Three early problems on size Ramsey numbers
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 43
year: '2023'
...
---
_id: '10335'
abstract:
- lang: eng
  text: "Van der Holst and Pendavingh introduced a graph parameter σ, which coincides
    with the more famous Colin de Verdière graph parameter μ for small values. However,
    the definition of a is much more geometric/topological directly reflecting embeddability
    properties of the graph. They proved μ(G) ≤ σ(G) + 2 and conjectured σ(G) ≤ σ(G)
    for any graph G. We confirm this conjecture. As far as we know, this is the first
    topological upper bound on σ(G) which is, in general, tight.\r\nEquality between
    μ and σ does not hold in general as van der Holst and Pendavingh showed that there
    is a graph G with μ(G) ≤ 18 and σ(G) ≥ 20. We show that the gap appears at much
    smaller values, namely, we exhibit a graph H for which μ(H) ≥ 7 and σ(H) ≥ 8.
    We also prove that, in general, the gap can be large: The incidence graphs Hq
    of finite projective planes of order q satisfy μ(Hq) ∈ O(q3/2) and σ(Hq) ≥ q2."
acknowledgement: 'V. K. gratefully acknowledges the support of Austrian Science Fund
  (FWF): P 30902-N35. This work was done mostly while he was employed at the University
  of Innsbruck. During the early stage of this research, V. K. was partially supported
  by Charles University project GAUK 926416. M. T. is supported by the grant no. 19-04113Y
  of the Czech Science Foundation(GA ˇCR) and partially supported by Charles University
  project UNCE/SCI/004.'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Vojtech
  full_name: Kaluza, Vojtech
  id: 21AE5134-9EAC-11EA-BEA2-D7BD3DDC885E
  last_name: Kaluza
  orcid: 0000-0002-2512-8698
- first_name: Martin
  full_name: Tancer, Martin
  id: 38AC689C-F248-11E8-B48F-1D18A9856A87
  last_name: Tancer
  orcid: 0000-0002-1191-6714
citation:
  ama: Kaluza V, Tancer M. Even maps, the Colin de Verdière number and representations
    of graphs. <i>Combinatorica</i>. 2022;42:1317-1345. doi:<a href="https://doi.org/10.1007/s00493-021-4443-7">10.1007/s00493-021-4443-7</a>
  apa: Kaluza, V., &#38; Tancer, M. (2022). Even maps, the Colin de Verdière number
    and representations of graphs. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-021-4443-7">https://doi.org/10.1007/s00493-021-4443-7</a>
  chicago: Kaluza, Vojtech, and Martin Tancer. “Even Maps, the Colin de Verdière Number
    and Representations of Graphs.” <i>Combinatorica</i>. Springer Nature, 2022. <a
    href="https://doi.org/10.1007/s00493-021-4443-7">https://doi.org/10.1007/s00493-021-4443-7</a>.
  ieee: V. Kaluza and M. Tancer, “Even maps, the Colin de Verdière number and representations
    of graphs,” <i>Combinatorica</i>, vol. 42. Springer Nature, pp. 1317–1345, 2022.
  ista: Kaluza V, Tancer M. 2022. Even maps, the Colin de Verdière number and representations
    of graphs. Combinatorica. 42, 1317–1345.
  mla: Kaluza, Vojtech, and Martin Tancer. “Even Maps, the Colin de Verdière Number
    and Representations of Graphs.” <i>Combinatorica</i>, vol. 42, Springer Nature,
    2022, pp. 1317–45, doi:<a href="https://doi.org/10.1007/s00493-021-4443-7">10.1007/s00493-021-4443-7</a>.
  short: V. Kaluza, M. Tancer, Combinatorica 42 (2022) 1317–1345.
corr_author: '1'
date_created: 2021-11-25T13:49:16Z
date_published: 2022-12-01T00:00:00Z
date_updated: 2024-10-09T20:53:51Z
day: '01'
ddc:
- '514'
- '516'
department:
- _id: UlWa
doi: 10.1007/s00493-021-4443-7
external_id:
  arxiv:
  - '1907.05055'
  isi:
  - '000798210100003'
intvolume: '        42'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: ' https://doi.org/10.48550/arXiv.1907.05055'
month: '12'
oa: 1
oa_version: Preprint
page: 1317-1345
publication: Combinatorica
publication_identifier:
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Even maps, the Colin de Verdière number and representations of graphs
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 42
year: '2022'
...
---
OA_place: repository
OA_type: green
_id: '22174'
abstract:
- lang: eng
  text: "The book graph B\r\n(k)\r\nn consists of n copies of Kk+1 joined along a
    common Kk. The Ramsey\r\nnumbers of B\r\n(k)\r\nn are known to have strong connections
    to the classical Ramsey numbers\r\nof cliques. Recently, the first author determined
    the asymptotic order of these Ramsey\r\nnumbers for fixed k, thus answering an
    old question of Erd˝os, Faudree, Rousseau, and\r\nSchelp. In this paper, we first
    provide a simpler proof of this theorem. Next, answering a\r\nquestion of the
    first author, we present a different proof that avoids the use of Szemer´edi’s\r\nregularity
    lemma, thus providing much tighter control on the error term. Finally, we prove\r\na
    conjecture of Nikiforov, Rousseau, and Schelp by showing that all extremal colorings
    for\r\nthis Ramsey problem are quasirandom"
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: David
  full_name: Conlon, David
  last_name: Conlon
- first_name: Jacob
  full_name: Fox, Jacob
  last_name: Fox
- first_name: Yuval
  full_name: Wigderson, Yuval
  id: 2d0023a0-1567-11f0-833d-d5c1e476d4b5
  last_name: Wigderson
citation:
  ama: Conlon D, Fox J, Wigderson Y. Ramsey numbers of books and quasirandomness.
    <i>Combinatorica</i>. 2022;42(3):309-363. doi:<a href="https://doi.org/10.1007/s00493-021-4409-9">10.1007/s00493-021-4409-9</a>
  apa: Conlon, D., Fox, J., &#38; Wigderson, Y. (2022). Ramsey numbers of books and
    quasirandomness. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-021-4409-9">https://doi.org/10.1007/s00493-021-4409-9</a>
  chicago: Conlon, David, Jacob Fox, and Yuval Wigderson. “Ramsey Numbers of Books
    and Quasirandomness.” <i>Combinatorica</i>. Springer Nature, 2022. <a href="https://doi.org/10.1007/s00493-021-4409-9">https://doi.org/10.1007/s00493-021-4409-9</a>.
  ieee: D. Conlon, J. Fox, and Y. Wigderson, “Ramsey numbers of books and quasirandomness,”
    <i>Combinatorica</i>, vol. 42, no. 3. Springer Nature, pp. 309–363, 2022.
  ista: Conlon D, Fox J, Wigderson Y. 2022. Ramsey numbers of books and quasirandomness.
    Combinatorica. 42(3), 309–363.
  mla: Conlon, David, et al. “Ramsey Numbers of Books and Quasirandomness.” <i>Combinatorica</i>,
    vol. 42, no. 3, Springer Nature, 2022, pp. 309–63, doi:<a href="https://doi.org/10.1007/s00493-021-4409-9">10.1007/s00493-021-4409-9</a>.
  short: D. Conlon, J. Fox, Y. Wigderson, Combinatorica 42 (2022) 309–363.
date_created: 2026-06-29T10:57:27Z
date_published: 2022-06-01T00:00:00Z
date_updated: 2026-07-14T08:57:12Z
day: '01'
doi: 10.1007/s00493-021-4409-9
extern: '1'
external_id:
  arxiv:
  - '2001.00407'
intvolume: '        42'
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2001.00407
month: '06'
oa: 1
oa_version: Preprint
page: 309-363
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Ramsey numbers of books and quasirandomness
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 42
year: '2022'
...
---
_id: '15275'
abstract:
- lang: eng
  text: In 1916, Schur introduced the Ramsey number r(3; m), which is the minimum
    integer n > 1 such that for any m-coloring of the edges of the complete graph
    Kn, there is a monochromatic copy of K3. He showed that r(3; m) ≤ O(m!), and a
    simple construction demonstrates that r(3; m) ≥ 2Ω(m). An old conjecture of Erdős
    states that r(3; m) = 2Θ(m). In this note, we prove the conjecture for m-colorings
    with bounded VC-dimension, that is, for m-colorings with the property that the
    set system induced by the neighborhoods of the vertices with respect to each color
    class has bounded VC-dimension.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Jacob
  full_name: Fox, Jacob
  last_name: Fox
- first_name: János
  full_name: Pach, János
  id: E62E3130-B088-11EA-B919-BF823C25FEA4
  last_name: Pach
- first_name: Andrew
  full_name: Suk, Andrew
  last_name: Suk
citation:
  ama: Fox J, Pach J, Suk A. Bounded VC-dimension implies the Schur-Erdős conjecture.
    <i>Combinatorica</i>. 2021;41(6):803-813. doi:<a href="https://doi.org/10.1007/s00493-021-4530-9">10.1007/s00493-021-4530-9</a>
  apa: Fox, J., Pach, J., &#38; Suk, A. (2021). Bounded VC-dimension implies the Schur-Erdős
    conjecture. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-021-4530-9">https://doi.org/10.1007/s00493-021-4530-9</a>
  chicago: Fox, Jacob, János Pach, and Andrew Suk. “Bounded VC-Dimension Implies the
    Schur-Erdős Conjecture.” <i>Combinatorica</i>. Springer Nature, 2021. <a href="https://doi.org/10.1007/s00493-021-4530-9">https://doi.org/10.1007/s00493-021-4530-9</a>.
  ieee: J. Fox, J. Pach, and A. Suk, “Bounded VC-dimension implies the Schur-Erdős
    conjecture,” <i>Combinatorica</i>, vol. 41, no. 6. Springer Nature, pp. 803–813,
    2021.
  ista: Fox J, Pach J, Suk A. 2021. Bounded VC-dimension implies the Schur-Erdős conjecture.
    Combinatorica. 41(6), 803–813.
  mla: Fox, Jacob, et al. “Bounded VC-Dimension Implies the Schur-Erdős Conjecture.”
    <i>Combinatorica</i>, vol. 41, no. 6, Springer Nature, 2021, pp. 803–13, doi:<a
    href="https://doi.org/10.1007/s00493-021-4530-9">10.1007/s00493-021-4530-9</a>.
  short: J. Fox, J. Pach, A. Suk, Combinatorica 41 (2021) 803–813.
date_created: 2024-04-03T07:59:57Z
date_published: 2021-11-20T00:00:00Z
date_updated: 2024-04-09T10:40:08Z
day: '20'
department:
- _id: HeEd
doi: 10.1007/s00493-021-4530-9
external_id:
  arxiv:
  - '1912.02342'
intvolume: '        41'
issue: '6'
keyword:
- Computational Mathematics
- Discrete Mathematics and Combinatorics
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.1912.02342
month: '11'
oa: 1
oa_version: Preprint
page: 803-813
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
status: public
title: Bounded VC-dimension implies the Schur-Erdős conjecture
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 41
year: '2021'
...
---
_id: '9582'
abstract:
- lang: eng
  text: The problem of finding dense induced bipartite subgraphs in H-free graphs
    has a long history, and was posed 30 years ago by Erdős, Faudree, Pach and Spencer.
    In this paper, we obtain several results in this direction. First we prove that
    any H-free graph with minimum degree at least d contains an induced bipartite
    subgraph of minimum degree at least cH log d/log log d, thus nearly confirming
    one and proving another conjecture of Esperet, Kang and Thomassé. Complementing
    this result, we further obtain optimal bounds for this problem in the case of
    dense triangle-free graphs, and we also answer a question of Erdœs, Janson, Łuczak
    and Spencer.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Matthew Alan
  full_name: Kwan, Matthew Alan
  id: 5fca0887-a1db-11eb-95d1-ca9d5e0453b3
  last_name: Kwan
  orcid: 0000-0002-4003-7567
- first_name: Shoham
  full_name: Letzter, Shoham
  last_name: Letzter
- first_name: Benny
  full_name: Sudakov, Benny
  last_name: Sudakov
- first_name: Tuan
  full_name: Tran, Tuan
  last_name: Tran
citation:
  ama: Kwan MA, Letzter S, Sudakov B, Tran T. Dense induced bipartite subgraphs in
    triangle-free graphs. <i>Combinatorica</i>. 2020;40(2):283-305. doi:<a href="https://doi.org/10.1007/s00493-019-4086-0">10.1007/s00493-019-4086-0</a>
  apa: Kwan, M. A., Letzter, S., Sudakov, B., &#38; Tran, T. (2020). Dense induced
    bipartite subgraphs in triangle-free graphs. <i>Combinatorica</i>. Springer. <a
    href="https://doi.org/10.1007/s00493-019-4086-0">https://doi.org/10.1007/s00493-019-4086-0</a>
  chicago: Kwan, Matthew Alan, Shoham Letzter, Benny Sudakov, and Tuan Tran. “Dense
    Induced Bipartite Subgraphs in Triangle-Free Graphs.” <i>Combinatorica</i>. Springer,
    2020. <a href="https://doi.org/10.1007/s00493-019-4086-0">https://doi.org/10.1007/s00493-019-4086-0</a>.
  ieee: M. A. Kwan, S. Letzter, B. Sudakov, and T. Tran, “Dense induced bipartite
    subgraphs in triangle-free graphs,” <i>Combinatorica</i>, vol. 40, no. 2. Springer,
    pp. 283–305, 2020.
  ista: Kwan MA, Letzter S, Sudakov B, Tran T. 2020. Dense induced bipartite subgraphs
    in triangle-free graphs. Combinatorica. 40(2), 283–305.
  mla: Kwan, Matthew Alan, et al. “Dense Induced Bipartite Subgraphs in Triangle-Free
    Graphs.” <i>Combinatorica</i>, vol. 40, no. 2, Springer, 2020, pp. 283–305, doi:<a
    href="https://doi.org/10.1007/s00493-019-4086-0">10.1007/s00493-019-4086-0</a>.
  short: M.A. Kwan, S. Letzter, B. Sudakov, T. Tran, Combinatorica 40 (2020) 283–305.
date_created: 2021-06-22T06:42:26Z
date_published: 2020-04-01T00:00:00Z
date_updated: 2023-02-23T14:01:45Z
day: '01'
doi: 10.1007/s00493-019-4086-0
extern: '1'
external_id:
  arxiv:
  - '1810.12144'
intvolume: '        40'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1810.12144
month: '04'
oa: 1
oa_version: Preprint
page: 283-305
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer
quality_controlled: '1'
scopus_import: '1'
status: public
title: Dense induced bipartite subgraphs in triangle-free graphs
type: journal_article
user_id: 6785fbc1-c503-11eb-8a32-93094b40e1cf
volume: 40
year: '2020'
...
---
_id: '7034'
abstract:
- lang: eng
  text: We find a graph of genus 5 and its drawing on the orientable surface of genus
    4 with every pair of independent edges crossing an even number of times. This
    shows that the strong Hanani–Tutte theorem cannot be extended to the orientable
    surface of genus 4. As a base step in the construction we use a counterexample
    to an extension of the unified Hanani–Tutte theorem on the torus.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Radoslav
  full_name: Fulek, Radoslav
  id: 39F3FFE4-F248-11E8-B48F-1D18A9856A87
  last_name: Fulek
  orcid: 0000-0001-8485-1774
- first_name: Jan
  full_name: Kynčl, Jan
  last_name: Kynčl
citation:
  ama: Fulek R, Kynčl J. Counterexample to an extension of the Hanani-Tutte theorem
    on the surface of genus 4. <i>Combinatorica</i>. 2019;39(6):1267-1279. doi:<a
    href="https://doi.org/10.1007/s00493-019-3905-7">10.1007/s00493-019-3905-7</a>
  apa: Fulek, R., &#38; Kynčl, J. (2019). Counterexample to an extension of the Hanani-Tutte
    theorem on the surface of genus 4. <i>Combinatorica</i>. Springer Nature. <a href="https://doi.org/10.1007/s00493-019-3905-7">https://doi.org/10.1007/s00493-019-3905-7</a>
  chicago: Fulek, Radoslav, and Jan Kynčl. “Counterexample to an Extension of the
    Hanani-Tutte Theorem on the Surface of Genus 4.” <i>Combinatorica</i>. Springer
    Nature, 2019. <a href="https://doi.org/10.1007/s00493-019-3905-7">https://doi.org/10.1007/s00493-019-3905-7</a>.
  ieee: R. Fulek and J. Kynčl, “Counterexample to an extension of the Hanani-Tutte
    theorem on the surface of genus 4,” <i>Combinatorica</i>, vol. 39, no. 6. Springer
    Nature, pp. 1267–1279, 2019.
  ista: Fulek R, Kynčl J. 2019. Counterexample to an extension of the Hanani-Tutte
    theorem on the surface of genus 4. Combinatorica. 39(6), 1267–1279.
  mla: Fulek, Radoslav, and Jan Kynčl. “Counterexample to an Extension of the Hanani-Tutte
    Theorem on the Surface of Genus 4.” <i>Combinatorica</i>, vol. 39, no. 6, Springer
    Nature, 2019, pp. 1267–79, doi:<a href="https://doi.org/10.1007/s00493-019-3905-7">10.1007/s00493-019-3905-7</a>.
  short: R. Fulek, J. Kynčl, Combinatorica 39 (2019) 1267–1279.
date_created: 2019-11-18T14:29:50Z
date_published: 2019-10-29T00:00:00Z
date_updated: 2025-04-14T13:52:37Z
day: '29'
department:
- _id: UlWa
doi: 10.1007/s00493-019-3905-7
ec_funded: 1
external_id:
  arxiv:
  - '1709.00508'
  isi:
  - '000493267200003'
intvolume: '        39'
isi: 1
issue: '6'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1709.00508
month: '10'
oa: 1
oa_version: Preprint
page: 1267-1279
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
- _id: 261FA626-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: M02281
  name: Eliminating intersections in drawings of graphs
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Counterexample to an extension of the Hanani-Tutte theorem on the surface of
  genus 4
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 39
year: '2019'
...
---
_id: '1173'
abstract:
- lang: eng
  text: We introduce the Voronoi functional of a triangulation of a finite set of
    points in the Euclidean plane and prove that among all geometric triangulations
    of the point set, the Delaunay triangulation maximizes the functional. This result
    neither extends to topological triangulations in the plane nor to geometric triangulations
    in three and higher dimensions.
acknowledgement: This research is partially supported by the Russian Government under
  the Mega Project 11.G34.31.0053, by the Toposys project FP7-ICT-318493-STREP, by
  ESF under the ACAT Research Network Programme, by RFBR grant 11-01-00735, and by
  NSF grants DMS-1101688, DMS-1400876.
article_processing_charge: No
arxiv: 1
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Alexey
  full_name: Glazyrin, Alexey
  last_name: Glazyrin
- first_name: Oleg
  full_name: Musin, Oleg
  last_name: Musin
- first_name: Anton
  full_name: Nikitenko, Anton
  id: 3E4FF1BA-F248-11E8-B48F-1D18A9856A87
  last_name: Nikitenko
  orcid: 0000-0002-0659-3201
citation:
  ama: Edelsbrunner H, Glazyrin A, Musin O, Nikitenko A. The Voronoi functional is
    maximized by the Delaunay triangulation in the plane. <i>Combinatorica</i>. 2017;37(5):887-910.
    doi:<a href="https://doi.org/10.1007/s00493-016-3308-y">10.1007/s00493-016-3308-y</a>
  apa: Edelsbrunner, H., Glazyrin, A., Musin, O., &#38; Nikitenko, A. (2017). The
    Voronoi functional is maximized by the Delaunay triangulation in the plane. <i>Combinatorica</i>.
    Springer. <a href="https://doi.org/10.1007/s00493-016-3308-y">https://doi.org/10.1007/s00493-016-3308-y</a>
  chicago: Edelsbrunner, Herbert, Alexey Glazyrin, Oleg Musin, and Anton Nikitenko.
    “The Voronoi Functional Is Maximized by the Delaunay Triangulation in the Plane.”
    <i>Combinatorica</i>. Springer, 2017. <a href="https://doi.org/10.1007/s00493-016-3308-y">https://doi.org/10.1007/s00493-016-3308-y</a>.
  ieee: H. Edelsbrunner, A. Glazyrin, O. Musin, and A. Nikitenko, “The Voronoi functional
    is maximized by the Delaunay triangulation in the plane,” <i>Combinatorica</i>,
    vol. 37, no. 5. Springer, pp. 887–910, 2017.
  ista: Edelsbrunner H, Glazyrin A, Musin O, Nikitenko A. 2017. The Voronoi functional
    is maximized by the Delaunay triangulation in the plane. Combinatorica. 37(5),
    887–910.
  mla: Edelsbrunner, Herbert, et al. “The Voronoi Functional Is Maximized by the Delaunay
    Triangulation in the Plane.” <i>Combinatorica</i>, vol. 37, no. 5, Springer, 2017,
    pp. 887–910, doi:<a href="https://doi.org/10.1007/s00493-016-3308-y">10.1007/s00493-016-3308-y</a>.
  short: H. Edelsbrunner, A. Glazyrin, O. Musin, A. Nikitenko, Combinatorica 37 (2017)
    887–910.
date_created: 2018-12-11T11:50:32Z
date_published: 2017-10-01T00:00:00Z
date_updated: 2025-06-04T08:44:44Z
day: '01'
department:
- _id: HeEd
doi: 10.1007/s00493-016-3308-y
ec_funded: 1
external_id:
  arxiv:
  - '1411.6337'
  isi:
  - '000418056000005'
intvolume: '        37'
isi: 1
issue: '5'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1411.6337
month: '10'
oa: 1
oa_version: Submitted Version
page: 887 - 910
project:
- _id: 255D761E-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '318493'
  name: Topological Complex Systems
publication: Combinatorica
publication_identifier:
  issn:
  - 0209-9683
publication_status: published
publisher: Springer
publist_id: '6182'
quality_controlled: '1'
scopus_import: '1'
status: public
title: The Voronoi functional is maximized by the Delaunay triangulation in the plane
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 37
year: '2017'
...
---
_id: '4053'
abstract:
- lang: eng
  text: We show that the maximum number of edges bounding m faces in an arrangement
    of n line segments in the plane is O(m2/3n2/3+nα(n)+nlog m). This improves a previous
    upper bound of Edelsbrunner et al. [5] and almost matches the best known lower
    bound which is Ω(m2/3n2/3+nα(n)). In addition, we show that the number of edges
    bounding any m faces in an arrangement of n line segments with a total of t intersecting
    pairs is O(m2/3t1/3+nα(t/n)+nmin{log m,log t/n}), almost matching the lower bound
    of Ω(m2/3t1/3+nα(t/n)) demonstrated in this paper.
article_processing_charge: No
article_type: original
author:
- first_name: Boris
  full_name: Aronov, Boris
  last_name: Aronov
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Leonidas
  full_name: Guibas, Leonidas
  last_name: Guibas
- first_name: Micha
  full_name: Sharir, Micha
  last_name: Sharir
citation:
  ama: Aronov B, Edelsbrunner H, Guibas L, Sharir M. The number of edges of many faces
    in a line segment arrangement. <i>Combinatorica</i>. 1992;12(3):261-274. doi:<a
    href="https://doi.org/10.1007/BF01285815">10.1007/BF01285815</a>
  apa: Aronov, B., Edelsbrunner, H., Guibas, L., &#38; Sharir, M. (1992). The number
    of edges of many faces in a line segment arrangement. <i>Combinatorica</i>. Springer.
    <a href="https://doi.org/10.1007/BF01285815">https://doi.org/10.1007/BF01285815</a>
  chicago: Aronov, Boris, Herbert Edelsbrunner, Leonidas Guibas, and Micha Sharir.
    “The Number of Edges of Many Faces in a Line Segment Arrangement.” <i>Combinatorica</i>.
    Springer, 1992. <a href="https://doi.org/10.1007/BF01285815">https://doi.org/10.1007/BF01285815</a>.
  ieee: B. Aronov, H. Edelsbrunner, L. Guibas, and M. Sharir, “The number of edges
    of many faces in a line segment arrangement,” <i>Combinatorica</i>, vol. 12, no.
    3. Springer, pp. 261–274, 1992.
  ista: Aronov B, Edelsbrunner H, Guibas L, Sharir M. 1992. The number of edges of
    many faces in a line segment arrangement. Combinatorica. 12(3), 261–274.
  mla: Aronov, Boris, et al. “The Number of Edges of Many Faces in a Line Segment
    Arrangement.” <i>Combinatorica</i>, vol. 12, no. 3, Springer, 1992, pp. 261–74,
    doi:<a href="https://doi.org/10.1007/BF01285815">10.1007/BF01285815</a>.
  short: B. Aronov, H. Edelsbrunner, L. Guibas, M. Sharir, Combinatorica 12 (1992)
    261–274.
date_created: 2018-12-11T12:06:40Z
date_published: 1992-09-01T00:00:00Z
date_updated: 2022-03-15T15:44:26Z
day: '01'
doi: 10.1007/BF01285815
extern: '1'
intvolume: '        12'
issue: '3'
language:
- iso: eng
main_file_link:
- url: https://link.springer.com/article/10.1007/BF01285815
month: '09'
oa_version: None
page: 261 - 274
publication: Combinatorica
publication_identifier:
  issn:
  - 0209-9683
publication_status: published
publisher: Springer
publist_id: '2074'
quality_controlled: '1'
scopus_import: '1'
status: public
title: The number of edges of many faces in a line segment arrangement
type: journal_article
user_id: ea97e931-d5af-11eb-85d4-e6957dddbf17
volume: 12
year: '1992'
...
---
_id: '4069'
abstract:
- lang: eng
  text: Let C be a cell complex in d-dimensional Euclidean space whose faces are obtained
    by orthogonal projection of the faces of a convex polytope in d + 1 dimensions.
    For example, the Delaunay triangulation of a finite point set is such a cell complex.
    This paper shows that the in front/behind relation defined for the faces of C
    with respect to any fixed viewpoint x is acyclic. This result has applications
    to hidden line/surface removal and other problems in computational geometry.
acknowledgement: Research reported in this paper was supported by the National Science
  Foundation under grant CCR-8714565.
article_processing_charge: No
article_type: original
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
citation:
  ama: Edelsbrunner H. An acyclicity theorem for cell complexes in d dimension. <i>Combinatorica</i>.
    1990;10(3):251-260. doi:<a href="https://doi.org/10.1007/BF02122779">10.1007/BF02122779</a>
  apa: Edelsbrunner, H. (1990). An acyclicity theorem for cell complexes in d dimension.
    <i>Combinatorica</i>. Springer. <a href="https://doi.org/10.1007/BF02122779">https://doi.org/10.1007/BF02122779</a>
  chicago: Edelsbrunner, Herbert. “An Acyclicity Theorem for Cell Complexes in d Dimension.”
    <i>Combinatorica</i>. Springer, 1990. <a href="https://doi.org/10.1007/BF02122779">https://doi.org/10.1007/BF02122779</a>.
  ieee: H. Edelsbrunner, “An acyclicity theorem for cell complexes in d dimension,”
    <i>Combinatorica</i>, vol. 10, no. 3. Springer, pp. 251–260, 1990.
  ista: Edelsbrunner H. 1990. An acyclicity theorem for cell complexes in d dimension.
    Combinatorica. 10(3), 251–260.
  mla: Edelsbrunner, Herbert. “An Acyclicity Theorem for Cell Complexes in d Dimension.”
    <i>Combinatorica</i>, vol. 10, no. 3, Springer, 1990, pp. 251–60, doi:<a href="https://doi.org/10.1007/BF02122779">10.1007/BF02122779</a>.
  short: H. Edelsbrunner, Combinatorica 10 (1990) 251–260.
date_created: 2018-12-11T12:06:45Z
date_published: 1990-09-01T00:00:00Z
date_updated: 2022-02-21T11:08:30Z
day: '01'
doi: 10.1007/BF02122779
extern: '1'
intvolume: '        10'
issue: '3'
language:
- iso: eng
main_file_link:
- url: https://link.springer.com/article/10.1007/BF02122779
month: '09'
oa_version: None
page: 251 - 260
publication: Combinatorica
publication_identifier:
  eissn:
  - 1439-6912
  issn:
  - 0209-9683
publication_status: published
publisher: Springer
publist_id: '2050'
quality_controlled: '1'
scopus_import: '1'
status: public
title: An acyclicity theorem for cell complexes in d dimension
type: journal_article
user_id: ea97e931-d5af-11eb-85d4-e6957dddbf17
volume: 10
year: '1990'
...
