Zobrazeno 1 - 10
of 26
pro vyhledávání: '"Carolyn Chun"'
Publikováno v:
Journal of Combinatorial Theory, Series B. 152:80-120
Generalizing a graph-theoretical result of Maffray to binary matroids, Oxley and Wetzler proved that a connected simple binary matroid M has no odd circuits other than triangles if and only if M is affine, M is isomorphic to M ( K 4 ) or F 7 , or M i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::dc27dfbb8ea05853e1e690a5d7e6c949
https://doi.org/10.1016/j.jctb.2021.09.006
https://doi.org/10.1016/j.jctb.2021.09.006
We find the excluded minors for the minor-closed class of lattice path polymatroids as a subclass of the minor-closed class of Boolean polymatroids. Like lattice path matroids and Boolean polymatroids, there are infinitely many excluded minors, but t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::24baa091473cfbed6152fa095a5fb7e3
http://arxiv.org/abs/2110.08434
http://arxiv.org/abs/2110.08434
Autor:
James Oxley, Carolyn Chun
Publikováno v:
Combinatorica. 39:825-845
Let $M$ be an internally $4$-connected binary matroid with every element in three triangles. Then $M$ has at least four elements $e$ such that si$(M/e)$ is internally 4-connected.
14 pages, 1 figure
14 pages, 1 figure
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6821eebdc3f1904ac0b8594e5f78e02e
https://doi.org/10.1007/s00493-019-3720-1
https://doi.org/10.1007/s00493-019-3720-1
Publikováno v:
Proceedings of the London Mathematical Society. 118:675-700
The mutually enriching relationship between graphs and matroids has motivated discoveries in both fields. In this paper, we exploit the similar relationship between embedded graphs and delta-matroids. There are well-known connections between geometri
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9d65cfede3fa344f0e7c6aadcf2aed45
https://doi.org/10.1112/plms.12190
https://doi.org/10.1112/plms.12190
Publikováno v:
Discrete Mathematics. 342:723-725
Let M be a matroid and e ∈ E ( M ) . The e -exchange basis graph of M has vertices labeled by bases of M , and two vertices are adjacent when the bases labeling them have symmetric difference { e , x } for some x ∈ E ( M ) . In this paper we show
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::34f848b86644814ea3adc5f20cebd5db
https://doi.org/10.1016/j.disc.2018.10.045
https://doi.org/10.1016/j.disc.2018.10.045
Publikováno v:
European Journal of Combinatorics. 60:10-20
We develop some basic tools to work with representable matroids of bounded tree-width and use them to prove that, for any prime power $q$ and constant $k$, the characteristic polynomial of any loopless, $GF(q)$-representable matroid with tree-width $
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f2b8a5d91d6f1ccec81981599dd709d0
https://doi.org/10.1016/j.ejc.2016.08.011
https://doi.org/10.1016/j.ejc.2016.08.011
Vf-safe delta-matroids have the desirable property of behaving well under certain duality operations. Several important classes of delta-matroids are known to be vf-safe, including the class of ribbon-graphic delta-matroids, which is related to the c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::43c1bc620b1f8fd6902df1f6cd132a54
https://eprints.bbk.ac.uk/id/eprint/27347/1/DeltaHiggsBonusRevisedFinalVersion.pdf
https://eprints.bbk.ac.uk/id/eprint/27347/1/DeltaHiggsBonusRevisedFinalVersion.pdf
Publikováno v:
Journal of Combinatorial Theory, Series B. 121:2-67
Let M be a binary matroid that is internally 4-connected, that is, M is 3-connected, and one side of every 3-separation is a triangle or a triad. Let N be an internally 4-connected proper minor of M. In this paper, we show that M has a proper interna
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9f3e1e61e7dc315569e99ec040a79749
https://doi.org/10.1016/j.jctb.2016.08.001
https://doi.org/10.1016/j.jctb.2016.08.001
Autor:
Carolyn Chun, Joseph E. Bonin
Publikováno v:
European Journal of Combinatorics. 89:103179
We introduce ideas that complement the many known connections between polymatroids and graph coloring. Given a hypergraph that satisfies certain conditions, we construct polymatroids, given as rank functions, that can be written as sums of rank funct
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f9cbde113823e37b8ae2b1ba4bf8bdab
https://doi.org/10.1016/j.ejc.2020.103179
https://doi.org/10.1016/j.ejc.2020.103179
In her paper "Generalized matroids and supermodular colourings", Tardos studied special delta-matroids obtained from sequences of Higgs lifts; these are the full Higgs lift delta-matroids that we treat and around which all of our results revolve. We
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d4929a11597adbefb4b6940ed71a11f7
http://arxiv.org/abs/1807.01375
http://arxiv.org/abs/1807.01375