Zobrazeno 1 - 10
of 138
pro vyhledávání: '"Matt DeVos"'
Publikováno v:
Journal of Combinatorial Theory, Series B. 149:198-221
In 1983, Bouchet proposed a conjecture that every flow-admissible signed graph admits a nowhere-zero 6-flow. Bouchet himself proved that such signed graphs admit nowhere-zero 216-flows and Zýka further proved that such signed graphs admit nowhere-ze
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8d255c40c7db6f511dcb38cb6d20e9fe
https://doi.org/10.1016/j.jctb.2020.04.008
https://doi.org/10.1016/j.jctb.2020.04.008
Publikováno v:
Graphs and Combinatorics. 36:1219-1246
The $$\gamma $$-graph of a graph G is the graph whose vertices are labelled by the minimum dominating sets of G, in which two vertices are adjacent when their corresponding minimum dominating sets (each of size $$\gamma (G)$$) intersect in a set of s
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6ae22ce2f936c761ed96c98229214ad9
https://doi.org/10.1007/s00373-020-02174-9
https://doi.org/10.1007/s00373-020-02174-9
Publikováno v:
Journal of Combinatorial Theory, Series B. 122:187-195
Tutte's famous 5-flow conjecture asserts that every bridgeless graph has a nowhere-zero 5-flow. Seymour proved that every such graph has a nowhere-zero 6-flow. Here we give (two versions of) a new proof of Seymour's Theorem. Both are roughly equal to
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::df9b2777a5acf653fd17099ce55dd2bb
https://doi.org/10.1016/j.jctb.2016.05.010
https://doi.org/10.1016/j.jctb.2016.05.010
Publikováno v:
The Electronic Journal of Combinatorics. 26
Let $G = (V,E)$ be a simple graph and let $\{R,B\}$ be a partition of $E$. We prove that whenever $|E| + \mathrm{min}\{ |R|, |B| \} > { |V| \choose 2 }$, there exists a subgraph of $G$ isomorphic to $K_3$ which contains edges from both $R$ and $B$. I
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ce7f1572fd43910d3c03e555a382f4e8
https://doi.org/10.37236/8193
https://doi.org/10.37236/8193
Publikováno v:
The Electronic Journal of Combinatorics. 26
Tutte initiated the study of nowhere-zero flows and proved the following fundamental theorem: For every graph $G$ there is a polynomial $f$ so that for every abelian group $\Gamma$ of order $n$, the number of nowhere-zero $\Gamma$-flows in $G$ is $f(
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b697a25e6d4b1c35c0bfa32227cdb623
https://doi.org/10.37236/7958
https://doi.org/10.37236/7958
We present a concept called the branch-depth of a connectivity function, that generalizes the tree-depth of graphs. Then we prove two theorems showing that this concept aligns closely with the notions of tree-depth and shrub-depth of graphs as follow
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0c241e43b887accfb3ec6725d6b779af
Autor:
Matt DeVos, Mahdieh Malekian
This paper gives a precise structure theorem for the class of graphs which do not contain $W_4$ as an immersion. This strengthens a previous result of Belmonte at al. that gives a rough description of this class. In fact, we prove a stronger theorem
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c73336f570452799088b8776933cc02c
http://arxiv.org/abs/1810.12863
http://arxiv.org/abs/1810.12863
Autor:
Sebastián González Hermosillo de la Maza, Daryl Funk, Bojan Mohar, Amanda Montejano, Matthew Drescher, Krystal Guo, Tony Huynh, Matt DeVos
Let $G$ be a simple $n$-vertex graph and $c$ be a colouring of $E(G)$ with $n$ colours, where each colour class has size at least $2$. We prove that $(G,c)$ contains a rainbow cycle of length at most $\lceil \frac{n}{2} \rceil$, which is best possibl
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f85a8edfca973961009377df4101d8f0
Publikováno v:
Discrete Mathematics. 338:9-35
We give a characterization of 3-connected graphs which are planar and forbid cube, octahedron, and $H$ minors, where $H$ is the graph which is one $\Delta-Y$ away from each of the cube and the octahedron. Next we say a graph is Feynman 5-split if no
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bc08defb79b885cfb8b987fa2298384e
https://doi.org/10.1016/j.disc.2014.10.001
https://doi.org/10.1016/j.disc.2014.10.001
Publikováno v:
Journal of Combinatorial Theory, Series B
We prove that every 3-edge-connected graph $G$ has a 3-flow $\phi$ with the property that $|\mathop{supp}(\phi)| \ge \frac{5}{6} |E(G)|$. The graph $K_4$ demonstrates that this $\frac{5}{6}$ ratio is best possible; there is an infinite family where $
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::624134c7583a76a862a75f7bfd35470f