---
OA_place: publisher
OA_type: hybrid
_id: '18753'
abstract:
- lang: eng
  text: "We continue a line of research which studies which hereditary families of
    digraphs have bounded dichromatic number. For a class of digraphs  C, a hero in
    \ C  is any digraph  H\r\n  such that  H -free digraphs in  C  have bounded dichromatic
    number. We show that if  F\r\n  is an oriented star of degree at least five, the
    only heroes for the class of  F -free digraphs are transitive tournaments. For
    oriented stars  F  of degree exactly four, we show the only heroes in  F -free
    digraphs are transitive tournaments, or possibly special joins of transitive tournaments.
    Aboulker et al. characterized the set of heroes of  {H,K1+P2→} -free digraphs
    almost completely, and we show the same characterization for the class of  {H,rK1+P3→}
    -free digraphs. Lastly, we show that if we forbid two \"valid\" orientations of
    brooms, then every transitive tournament is a hero for this class of digraphs."
acknowledgement: "We thank the anonymous referees for their careful proofreading which
  helped improve the presentation of this paper. We also thank one of the anonymous
  referees for pointing out our construction implies Theorem 1.7!\r\nBenjamin Moore
  finished this project while a postdoctoral researcher at Charles University, and
  was supported by project 22-17398S (Flows and cycles in graphs on surfaces) of the
  Czech Science Foundation. Benjamin Moore is currently funded by RANDSTRUCT No. 101076777,
  and appreciates the gracious support. We acknowledge the support of the Natural
  Sciences and Engineering Research Council of Canada (NSERC), [funding reference
  number RGPIN-2020-03912]. Cette recherche a été financée par le Conseil de recherches
  en sciences naturelles et en génie du Canada (CRSNG), [numéro de référence RGPIN-2020-03912].
  This project was funded in part by the Government of Ontario ."
article_number: '104104'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: Alvaro
  full_name: Carbonero, Alvaro
  last_name: Carbonero
- first_name: Hidde
  full_name: Koerts, Hidde
  last_name: Koerts
- first_name: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
- first_name: Sophie
  full_name: Spirkl, Sophie
  last_name: Spirkl
citation:
  ama: Carbonero A, Koerts H, Moore B, Spirkl S. On heroes in digraphs with forbidden
    induced forests. <i>European Journal of Combinatorics</i>. 2025;125. doi:<a href="https://doi.org/10.1016/j.ejc.2024.104104">10.1016/j.ejc.2024.104104</a>
  apa: Carbonero, A., Koerts, H., Moore, B., &#38; Spirkl, S. (2025). On heroes in
    digraphs with forbidden induced forests. <i>European Journal of Combinatorics</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.ejc.2024.104104">https://doi.org/10.1016/j.ejc.2024.104104</a>
  chicago: Carbonero, Alvaro, Hidde Koerts, Benjamin Moore, and Sophie Spirkl. “On
    Heroes in Digraphs with Forbidden Induced Forests.” <i>European Journal of Combinatorics</i>.
    Elsevier, 2025. <a href="https://doi.org/10.1016/j.ejc.2024.104104">https://doi.org/10.1016/j.ejc.2024.104104</a>.
  ieee: A. Carbonero, H. Koerts, B. Moore, and S. Spirkl, “On heroes in digraphs with
    forbidden induced forests,” <i>European Journal of Combinatorics</i>, vol. 125.
    Elsevier, 2025.
  ista: Carbonero A, Koerts H, Moore B, Spirkl S. 2025. On heroes in digraphs with
    forbidden induced forests. European Journal of Combinatorics. 125, 104104.
  mla: Carbonero, Alvaro, et al. “On Heroes in Digraphs with Forbidden Induced Forests.”
    <i>European Journal of Combinatorics</i>, vol. 125, 104104, Elsevier, 2025, doi:<a
    href="https://doi.org/10.1016/j.ejc.2024.104104">10.1016/j.ejc.2024.104104</a>.
  short: A. Carbonero, H. Koerts, B. Moore, S. Spirkl, European Journal of Combinatorics
    125 (2025).
corr_author: '1'
date_created: 2025-01-05T23:01:55Z
date_published: 2025-03-01T00:00:00Z
date_updated: 2025-05-19T14:06:00Z
day: '01'
ddc:
- '510'
department:
- _id: MaKw
doi: 10.1016/j.ejc.2024.104104
external_id:
  arxiv:
  - '2306.04710'
  isi:
  - '001400113700001'
file:
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  creator: dernst
  date_created: 2025-04-16T09:16:25Z
  date_updated: 2025-04-16T09:16:25Z
  file_id: '19577'
  file_name: 2025_EuropJournCombinatorics_Carbonero.pdf
  file_size: 1110657
  relation: main_file
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file_date_updated: 2025-04-16T09:16:25Z
fulldoi: https://doi.org/10.1016/j.ejc.2024.104104
has_accepted_license: '1'
intvolume: '       125'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '03'
oa: 1
oa_version: Published Version
project:
- _id: bd95085b-d553-11ed-ba76-e55d3349be45
  grant_number: '101076777'
  name: Randomness and structure in combinatorics
publication: European Journal of Combinatorics
publication_identifier:
  issn:
  - 0195-6698
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: On heroes in digraphs with forbidden induced forests
tmp:
  image: /images/cc_by.png
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  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 125
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
_id: '19002'
abstract:
- lang: eng
  text: "A k-subcolouring of a graph G is a function f : V (G) → {0,...,k − 1} such
    that the set of\r\nvertices coloured i induce a disjoint union of cliques. The
    subchromatic number, χsub(G),\r\nis the minimum k such that G admits a k-subcolouring.
    Nešetril, ˇ Ossona de Mendez,\r\nPilipczuk, and Zhu (2020), recently raised the
    problem of finding tight upper bounds for\r\nχsub(G2) when G is planar. We show
    that χsub(G2) ≤ 43 when G is planar, improving\r\ntheir bound of 135. We give
    even better bounds when the planar graph G has larger girth.\r\nMoreover, we show
    that χsub(G3) ≤ 95, improving the previous bound of 364. For these\r\nwe adapt
    some recent techniques of Almulhim and Kierstead (2022), while also extending\r\nthe
    decompositions of triangulated planar graphs of Van den Heuvel, Ossona de Mendez,\r\nQuiroz,
    Rabinovich and Siebertz (2017), to planar graphs of arbitrary girth. Note that
    these\r\ndecompositions are the precursors of the graph product structure theorem
    of planar graphs.\r\nWe give improved bounds for χsub(Gp) for all p ≥ 2, whenever
    G has bounded treewidth,\r\nbounded simple treewidth, bounded genus, or excludes
    a clique or biclique as a minor.\r\nFor this we introduce a family of parameters
    which form a gradation between the strong\r\nand the weak colouring numbers. We
    give upper bounds for these parameters for graphs\r\ncoming from such classes.\r\nFinally,
    we give a 2-approximation algorithm for the subchromatic number of graphs\r\nhaving
    a layering in which each layer has bounded cliquewidth and this layering is\r\ncomputable
    in polynomial time (like the class of all dth powers of planar graphs, for fixed\r\nd).
    This algorithm works even if the power p and the graph G is unknown."
acknowledgement: We thank an anonymous referee for pointing out an error in an earlier
  version of Theorem 3.1. We also thank an anonymous referee for pointing out numerous
  typos in an earlier version of the paper.
article_number: '114377'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Pedro P.
  full_name: Cortés, Pedro P.
  last_name: Cortés
- first_name: Pankaj
  full_name: Kumar, Pankaj
  last_name: Kumar
- first_name: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
- first_name: Patrice
  full_name: Ossona de Mendez, Patrice
  last_name: Ossona de Mendez
- first_name: Daniel A.
  full_name: Quiroz, Daniel A.
  last_name: Quiroz
citation:
  ama: Cortés PP, Kumar P, Moore B, Ossona de Mendez P, Quiroz DA. Subchromatic numbers
    of powers of graphs with excluded minors. <i>Discrete Mathematics</i>. 2025;348(4).
    doi:<a href="https://doi.org/10.1016/j.disc.2024.114377">10.1016/j.disc.2024.114377</a>
  apa: Cortés, P. P., Kumar, P., Moore, B., Ossona de Mendez, P., &#38; Quiroz, D.
    A. (2025). Subchromatic numbers of powers of graphs with excluded minors. <i>Discrete
    Mathematics</i>. Elsevier. <a href="https://doi.org/10.1016/j.disc.2024.114377">https://doi.org/10.1016/j.disc.2024.114377</a>
  chicago: Cortés, Pedro P., Pankaj Kumar, Benjamin Moore, Patrice Ossona de Mendez,
    and Daniel A. Quiroz. “Subchromatic Numbers of Powers of Graphs with Excluded
    Minors.” <i>Discrete Mathematics</i>. Elsevier, 2025. <a href="https://doi.org/10.1016/j.disc.2024.114377">https://doi.org/10.1016/j.disc.2024.114377</a>.
  ieee: P. P. Cortés, P. Kumar, B. Moore, P. Ossona de Mendez, and D. A. Quiroz, “Subchromatic
    numbers of powers of graphs with excluded minors,” <i>Discrete Mathematics</i>,
    vol. 348, no. 4. Elsevier, 2025.
  ista: Cortés PP, Kumar P, Moore B, Ossona de Mendez P, Quiroz DA. 2025. Subchromatic
    numbers of powers of graphs with excluded minors. Discrete Mathematics. 348(4),
    114377.
  mla: Cortés, Pedro P., et al. “Subchromatic Numbers of Powers of Graphs with Excluded
    Minors.” <i>Discrete Mathematics</i>, vol. 348, no. 4, 114377, Elsevier, 2025,
    doi:<a href="https://doi.org/10.1016/j.disc.2024.114377">10.1016/j.disc.2024.114377</a>.
  short: P.P. Cortés, P. Kumar, B. Moore, P. Ossona de Mendez, D.A. Quiroz, Discrete
    Mathematics 348 (2025).
corr_author: '1'
date_created: 2025-02-05T06:51:08Z
date_published: 2025-04-01T00:00:00Z
date_updated: 2025-09-30T10:25:15Z
day: '01'
ddc:
- '510'
department:
- _id: MaKw
doi: 10.1016/j.disc.2024.114377
external_id:
  arxiv:
  - '2306.02195'
  isi:
  - '001401656900001'
file:
- access_level: open_access
  checksum: 6723cbb02b6aea0d05f37d167da00c03
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  date_created: 2025-05-05T12:56:12Z
  date_updated: 2025-05-05T12:56:12Z
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  relation: main_file
  success: 1
file_date_updated: 2025-05-05T12:56:12Z
fulldoi: https://doi.org/10.1016/j.disc.2024.114377
has_accepted_license: '1'
intvolume: '       348'
isi: 1
issue: '4'
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
publication: Discrete Mathematics
publication_identifier:
  issn:
  - 0012-365X
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Subchromatic numbers of powers of graphs with excluded minors
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
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  short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 348
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
_id: '19879'
abstract:
- lang: eng
  text: We consider the 4-precoloring extension problem in planar near-Eulerian- triangulations,
    i.e., plane graphs where all faces except possibly for the outer one have length
    three, all vertices not incident with the outer face have even degree, and exactly
    the vertices incident with the outer face are precolored. We give a necessary
    topological condition for the precoloring to extend, and give a complete characterization
    when the outer face has length at most five and when all vertices of the outer
    face have odd degree and are colored using only three colors.
acknowledgement: Supported by project 22-17398S (Flows and cycles in graphs on surfaces)
  of Czech Science Foundation. An extended abstract appeared in Proceedings of the
  12th European Conference on Combinatorics, Graph Theory and Applications (EUROCOMB’23)
article_number: '104138'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Zdeněk
  full_name: Dvořák, Zdeněk
  last_name: Dvořák
- first_name: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
- first_name: Michaela
  full_name: Seifrtová, Michaela
  last_name: Seifrtová
- first_name: Robert
  full_name: Šámal, Robert
  last_name: Šámal
citation:
  ama: Dvořák Z, Moore B, Seifrtová M, Šámal R. Precoloring extension in planar near-Eulerian-triangulations.
    <i>European Journal of Combinatorics</i>. 2025;127. doi:<a href="https://doi.org/10.1016/j.ejc.2025.104138">10.1016/j.ejc.2025.104138</a>
  apa: Dvořák, Z., Moore, B., Seifrtová, M., &#38; Šámal, R. (2025). Precoloring extension
    in planar near-Eulerian-triangulations. <i>European Journal of Combinatorics</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.ejc.2025.104138">https://doi.org/10.1016/j.ejc.2025.104138</a>
  chicago: Dvořák, Zdeněk, Benjamin Moore, Michaela Seifrtová, and Robert Šámal. “Precoloring
    Extension in Planar Near-Eulerian-Triangulations.” <i>European Journal of Combinatorics</i>.
    Elsevier, 2025. <a href="https://doi.org/10.1016/j.ejc.2025.104138">https://doi.org/10.1016/j.ejc.2025.104138</a>.
  ieee: Z. Dvořák, B. Moore, M. Seifrtová, and R. Šámal, “Precoloring extension in
    planar near-Eulerian-triangulations,” <i>European Journal of Combinatorics</i>,
    vol. 127. Elsevier, 2025.
  ista: Dvořák Z, Moore B, Seifrtová M, Šámal R. 2025. Precoloring extension in planar
    near-Eulerian-triangulations. European Journal of Combinatorics. 127, 104138.
  mla: Dvořák, Zdeněk, et al. “Precoloring Extension in Planar Near-Eulerian-Triangulations.”
    <i>European Journal of Combinatorics</i>, vol. 127, 104138, Elsevier, 2025, doi:<a
    href="https://doi.org/10.1016/j.ejc.2025.104138">10.1016/j.ejc.2025.104138</a>.
  short: Z. Dvořák, B. Moore, M. Seifrtová, R. Šámal, European Journal of Combinatorics
    127 (2025).
corr_author: '1'
date_created: 2025-06-23T13:54:46Z
date_published: 2025-06-01T00:00:00Z
date_updated: 2025-09-30T13:42:59Z
day: '01'
ddc:
- '510'
department:
- _id: MaKw
doi: 10.1016/j.ejc.2025.104138
external_id:
  arxiv:
  - '2312.13061'
  isi:
  - '001443061400001'
file:
- access_level: open_access
  checksum: 8b3585df45b25091fba9bee9854b7d01
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  creator: dernst
  date_created: 2025-06-24T06:33:30Z
  date_updated: 2025-06-24T06:33:30Z
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file_date_updated: 2025-06-24T06:33:30Z
fulldoi: https://doi.org/10.1016/j.ejc.2025.104138
has_accepted_license: '1'
intvolume: '       127'
isi: 1
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
publication: European Journal of Combinatorics
publication_identifier:
  issn:
  - 0195-6698
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Precoloring extension in planar near-Eulerian-triangulations
tmp:
  image: /images/cc_by.png
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  short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 127
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
_id: '20007'
abstract:
- lang: eng
  text: 'There is no known polynomial-time algorithm for graph isomorphism testing,
    but elementary combinatorial “refinement” algorithms seem to be very efficient
    in practice. Some philosophical justification for this phenomenon is provided
    by a classical theorem of Babai, Erdős and Selkow: an extremely simple polynomial-time
    combinatorial algorithm (variously known as “naïve refinement”, “naïve vertex
    classification”, “colour refinement” or the “1-dimensional Weisfeiler–Leman algorithm”)
    yields a so-called canonical labelling scheme for “almost all graphs”. More precisely,
    for a typical outcome of a random graph G(n,1/2), this simple combinatorial algorithm
    assigns labels to vertices in a way that easily permits isomorphism-testing against
    any other graph.'
acknowledgement: All authors were supported by ERC Starting Grant “RANDSTRUCT” No.
  101076777. Michael Anastos was also supported in part by the Austrian Science Fund
  (FWF)[10.55776/ESP3863424] and by the European Union’s Horizon 2020 research and
  innovation programme under the Marie Skłodowska-Curie grant agreement No. 101034413.
  For Open Access purposes, the authors have applied a CC BY public copyright license
  to any author accepted manuscript version arising from this submission.
article_processing_charge: Yes (via OA deal)
arxiv: 1
author:
- first_name: Michael
  full_name: Anastos, Michael
  id: 0b2a4358-bb35-11ec-b7b9-e3279b593dbb
  last_name: Anastos
- 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: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
citation:
  ama: 'Anastos M, Kwan MA, Moore B. Smoothed analysis for graph isomorphism. In:
    <i>Proceedings of the 57th Annual ACM Symposium on Theory of Computing</i>. Association
    for Computing Machinery; 2025:2098-2106. doi:<a href="https://doi.org/10.1145/3717823.3718173">10.1145/3717823.3718173</a>'
  apa: 'Anastos, M., Kwan, M. A., &#38; Moore, B. (2025). Smoothed analysis for graph
    isomorphism. In <i>Proceedings of the 57th Annual ACM Symposium on Theory of Computing</i>
    (pp. 2098–2106). Prague, Czechia: Association for Computing Machinery. <a href="https://doi.org/10.1145/3717823.3718173">https://doi.org/10.1145/3717823.3718173</a>'
  chicago: Anastos, Michael, Matthew Alan Kwan, and Benjamin Moore. “Smoothed Analysis
    for Graph Isomorphism.” In <i>Proceedings of the 57th Annual ACM Symposium on
    Theory of Computing</i>, 2098–2106. Association for Computing Machinery, 2025.
    <a href="https://doi.org/10.1145/3717823.3718173">https://doi.org/10.1145/3717823.3718173</a>.
  ieee: M. Anastos, M. A. Kwan, and B. Moore, “Smoothed analysis for graph isomorphism,”
    in <i>Proceedings of the 57th Annual ACM Symposium on Theory of Computing</i>,
    Prague, Czechia, 2025, pp. 2098–2106.
  ista: 'Anastos M, Kwan MA, Moore B. 2025. Smoothed analysis for graph isomorphism.
    Proceedings of the 57th Annual ACM Symposium on Theory of Computing. STOC: Symposium
    on Theory of Computing, 2098–2106.'
  mla: Anastos, Michael, et al. “Smoothed Analysis for Graph Isomorphism.” <i>Proceedings
    of the 57th Annual ACM Symposium on Theory of Computing</i>, Association for Computing
    Machinery, 2025, pp. 2098–106, doi:<a href="https://doi.org/10.1145/3717823.3718173">10.1145/3717823.3718173</a>.
  short: M. Anastos, M.A. Kwan, B. Moore, in:, Proceedings of the 57th Annual ACM
    Symposium on Theory of Computing, Association for Computing Machinery, 2025, pp.
    2098–2106.
conference:
  end_date: 2025-06-27
  location: Prague, Czechia
  name: 'STOC: Symposium on Theory of Computing'
  start_date: 2025-06-23
corr_author: '1'
date_created: 2025-07-13T22:01:23Z
date_published: 2025-06-15T00:00:00Z
date_updated: 2025-07-14T06:33:50Z
day: '15'
ddc:
- '000'
department:
- _id: MaKw
doi: 10.1145/3717823.3718173
ec_funded: 1
external_id:
  arxiv:
  - '2410.06095'
file:
- access_level: open_access
  checksum: cf0ab9cb9c6abda188de13dc3f9a4c9b
  content_type: application/pdf
  creator: dernst
  date_created: 2025-07-14T06:13:10Z
  date_updated: 2025-07-14T06:13:10Z
  file_id: '20012'
  file_name: 2025_STOC_Anastos.pdf
  file_size: 706445
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  success: 1
file_date_updated: 2025-07-14T06:13:10Z
fulldoi: https://doi.org/10.1145/3717823.3718173
has_accepted_license: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: 2098-2106
project:
- _id: bd95085b-d553-11ed-ba76-e55d3349be45
  grant_number: '101076777'
  name: Randomness and structure in combinatorics
- _id: fc2ed2f7-9c52-11eb-aca3-c01059dda49c
  call_identifier: H2020
  grant_number: '101034413'
  name: 'IST-BRIDGE: International postdoctoral program'
- _id: 8f906bd2-16d5-11f0-9cad-e07be8aa9ac9
  grant_number: ESP3863424
  name: Combinatorial Optimisation Problems on Sparse Random Graphs
publication: Proceedings of the 57th Annual ACM Symposium on Theory of Computing
publication_identifier:
  isbn:
  - '9798400715105'
  issn:
  - 0737-8017
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: Smoothed analysis for graph isomorphism
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type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '20320'
abstract:
- lang: eng
  text: "The pseudoforest version of the Strong Nine Dragon Tree Conjecture states
    that if a graph G has maximum average degree mad(G) = 2 maxH⊆G e(H)/v(H) at most
    2(k + d/d+k+1), then it has a decomposition into k + 1 pseudoforests where in
    one pseudoforest F the components of F have at most d edges. This was proven in
    2020 in Grout and Moore (2020). We strengthen this\r\ntheorem by showing that
    we can find such a decomposition where additionally F is acyclic, the diameter
    of the components of F is at most 2ℓ + 2, where ℓ =⌊d−1/k+1⌋, and at most 2ℓ +
    1 if\r\nd ≡ 1 mod (k + 1). Furthermore, for any component K of F and any z ∈ N,
    we have diam(K) ≤ 2z if e(K) ≥ d − z(k − 1) + 1. We also show that both diameter
    bounds are best possible as an\r\nextension for both the Strong Nine Dragon Tree
    Conjecture for pseudoforests and its original conjecture for forests. In fact,
    they are still optimal even if we only enforce F to have any constant maximum
    degree, instead of enforcing every component of F to have at most d edges."
acknowledgement: This work was completed while Benjamin Moore was a postdoc at Charles
  University, supported by project 22-17398S (Flows and cycles in graphs on surfaces)
  of Czech Science Foundation, Czechia.
article_number: '104214'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Sebastian
  full_name: Mies, Sebastian
  last_name: Mies
- first_name: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
- first_name: Evelyne
  full_name: Smith-Roberge, Evelyne
  last_name: Smith-Roberge
citation:
  ama: Mies S, Moore B, Smith-Roberge E. Beyond the pseudoforest strong Nine Dragon
    Tree theorem. <i>European Journal of Combinatorics</i>. 2025;130(12). doi:<a href="https://doi.org/10.1016/j.ejc.2025.104214">10.1016/j.ejc.2025.104214</a>
  apa: Mies, S., Moore, B., &#38; Smith-Roberge, E. (2025). Beyond the pseudoforest
    strong Nine Dragon Tree theorem. <i>European Journal of Combinatorics</i>. Elsevier.
    <a href="https://doi.org/10.1016/j.ejc.2025.104214">https://doi.org/10.1016/j.ejc.2025.104214</a>
  chicago: Mies, Sebastian, Benjamin Moore, and Evelyne Smith-Roberge. “Beyond the
    Pseudoforest Strong Nine Dragon Tree Theorem.” <i>European Journal of Combinatorics</i>.
    Elsevier, 2025. <a href="https://doi.org/10.1016/j.ejc.2025.104214">https://doi.org/10.1016/j.ejc.2025.104214</a>.
  ieee: S. Mies, B. Moore, and E. Smith-Roberge, “Beyond the pseudoforest strong Nine
    Dragon Tree theorem,” <i>European Journal of Combinatorics</i>, vol. 130, no.
    12. Elsevier, 2025.
  ista: Mies S, Moore B, Smith-Roberge E. 2025. Beyond the pseudoforest strong Nine
    Dragon Tree theorem. European Journal of Combinatorics. 130(12), 104214.
  mla: Mies, Sebastian, et al. “Beyond the Pseudoforest Strong Nine Dragon Tree Theorem.”
    <i>European Journal of Combinatorics</i>, vol. 130, no. 12, 104214, Elsevier,
    2025, doi:<a href="https://doi.org/10.1016/j.ejc.2025.104214">10.1016/j.ejc.2025.104214</a>.
  short: S. Mies, B. Moore, E. Smith-Roberge, European Journal of Combinatorics 130
    (2025).
corr_author: '1'
date_created: 2025-09-10T05:36:50Z
date_published: 2025-12-01T00:00:00Z
date_updated: 2025-12-30T10:19:10Z
day: '01'
ddc:
- '500'
department:
- _id: MaKw
doi: 10.1016/j.ejc.2025.104214
external_id:
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  - '001529769300002'
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fulldoi: https://doi.org/10.1016/j.ejc.2025.104214
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intvolume: '       130'
isi: 1
issue: '12'
language:
- iso: eng
month: '12'
oa: 1
oa_version: Published Version
publication: European Journal of Combinatorics
publication_identifier:
  issn:
  - 0195-6698
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Beyond the pseudoforest strong Nine Dragon Tree theorem
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: 130
year: '2025'
...
---
_id: '15163'
abstract:
- lang: eng
  text: For some k∈Z≥0∪{∞}, we call a linear forest k-bounded if each of its components
    has at most k edges. We will say a (k,ℓ)-bounded linear forest decomposition of
    a graph G is a partition of E(G) into the edge sets of two linear forests Fk,Fℓ
    where Fk is k-bounded and Fℓ is ℓ-bounded. We show that the problem of deciding
    whether a given graph has such a decomposition is NP-complete if both k and ℓ
    are at least 2, NP-complete if k≥9 and ℓ=1, and is in P for (k,ℓ)=(2,1). Before
    this, the only known NP-complete cases were the (2,2) and (3,3) cases. Our hardness
    result answers a question of Bermond et al. from 1984. We also show that planar
    graphs of girth at least nine decompose into a linear forest and a matching, which
    in particular is stronger than 3-edge-colouring such graphs.
acknowledgement: We wish to thank Dániel Marx and András Sebő for making us aware
  of the results in [8] and some clarifications on them.
article_number: '113962'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Rutger
  full_name: Campbell, Rutger
  last_name: Campbell
- first_name: Florian
  full_name: Hörsch, Florian
  last_name: Hörsch
- first_name: Benjamin
  full_name: Moore, Benjamin
  id: 6dc1a1be-bf1c-11ed-8d2b-d044840f49d6
  last_name: Moore
citation:
  ama: Campbell R, Hörsch F, Moore B. Decompositions into two linear forests of bounded
    lengths. <i>Discrete Mathematics</i>. 2024;347(6). doi:<a href="https://doi.org/10.1016/j.disc.2024.113962">10.1016/j.disc.2024.113962</a>
  apa: Campbell, R., Hörsch, F., &#38; Moore, B. (2024). Decompositions into two linear
    forests of bounded lengths. <i>Discrete Mathematics</i>. Elsevier. <a href="https://doi.org/10.1016/j.disc.2024.113962">https://doi.org/10.1016/j.disc.2024.113962</a>
  chicago: Campbell, Rutger, Florian Hörsch, and Benjamin Moore. “Decompositions into
    Two Linear Forests of Bounded Lengths.” <i>Discrete Mathematics</i>. Elsevier,
    2024. <a href="https://doi.org/10.1016/j.disc.2024.113962">https://doi.org/10.1016/j.disc.2024.113962</a>.
  ieee: R. Campbell, F. Hörsch, and B. Moore, “Decompositions into two linear forests
    of bounded lengths,” <i>Discrete Mathematics</i>, vol. 347, no. 6. Elsevier, 2024.
  ista: Campbell R, Hörsch F, Moore B. 2024. Decompositions into two linear forests
    of bounded lengths. Discrete Mathematics. 347(6), 113962.
  mla: Campbell, Rutger, et al. “Decompositions into Two Linear Forests of Bounded
    Lengths.” <i>Discrete Mathematics</i>, vol. 347, no. 6, 113962, Elsevier, 2024,
    doi:<a href="https://doi.org/10.1016/j.disc.2024.113962">10.1016/j.disc.2024.113962</a>.
  short: R. Campbell, F. Hörsch, B. Moore, Discrete Mathematics 347 (2024).
corr_author: '1'
date_created: 2024-03-24T23:00:58Z
date_published: 2024-06-01T00:00:00Z
date_updated: 2025-09-04T13:10:26Z
day: '01'
department:
- _id: MaKw
doi: 10.1016/j.disc.2024.113962
external_id:
  arxiv:
  - '2301.11615'
  isi:
  - '001226893800001'
fulldoi: https://doi.org/10.1016/j.disc.2024.113962
intvolume: '       347'
isi: 1
issue: '6'
language:
- iso: eng
main_file_link:
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  url: https://doi.org/10.48550/arXiv.2301.11615
month: '06'
oa: 1
oa_version: Preprint
publication: Discrete Mathematics
publication_identifier:
  issn:
  - 0012-365X
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Decompositions into two linear forests of bounded lengths
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 347
year: '2024'
...
