Zobrazeno 1 - 10
of 35
pro vyhledávání: '"Yoo, Youngho"'
Autor:
Kwon, O-joung, Yoo, Youngho
We characterize the obstructions to the Erd\H{o}s-P\'osa property of $A$-paths in unoriented group-labelled graphs. As a result, we prove that for every finite abelian group $\Gamma$ and for every subset $\Lambda$ of $\Gamma$, the family of $\Gamma$-
Externí odkaz:
http://arxiv.org/abs/2411.05372
Autor:
Liu, Chun-Hung, Yoo, Youngho
Motivated by Hadwiger's conjecture and related problems for list-coloring, we study graphs $H$ for which every graph with minimum degree at least $|V(H)|-1$ contains $H$ as a minor. We prove that a large class of apex-outerplanar graphs satisfies thi
Externí odkaz:
http://arxiv.org/abs/2403.11470
Autor:
Borgwardt, Steffen, Buchanan, Calum, Culver, Eric, Frederickson, Bryce, Rombach, Puck, Yoo, Youngho
We introduce and study "path odd-covers", a weakening of Gallai's path decomposition problem and a strengthening of the linear arboricity problem. The "path odd-cover number" $p_2(G)$ of a graph $G$ is the minimum cardinality of a collection of paths
Externí odkaz:
http://arxiv.org/abs/2306.06487
Autor:
Black, Alexander E., Liu, Kevin, Mcdonough, Alex, Nelson, Garrett, Wigal, Michael C., Yin, Mei, Yoo, Youngho
A tanglegram consists of two rooted binary trees and a perfect matching between their leaves, and a planar tanglegram is one that admits a layout with no crossings. We show that the problem of generating planar tanglegrams uniformly at random reduces
Externí odkaz:
http://arxiv.org/abs/2304.05318
In 1965, Erd\H{o}s and P\'{o}sa proved that there is a duality between the maximum size of a packing of cycles and the minimum size of a vertex set hitting all cycles. Such a duality does not hold for odd cycles, and Dejter and Neumann-Lara asked in
Externí odkaz:
http://arxiv.org/abs/2209.09488
We prove that every simple 2-connected subcubic graph on $n$ vertices with $n_2$ vertices of degree 2 has a TSP walk of length at most $\frac{5n+n_2}{4}-1$, confirming a conjecture of Dvo\v{r}\'ak, Kr\'al', and Mohar. This bound is best possible; the
Externí odkaz:
http://arxiv.org/abs/2112.06278
Autor:
Thomas, Robin, Yoo, Youngho
Publikováno v:
J. Combin. Theory Ser. B 160 (2023), 114-143
It is known that $A$-paths of length $0$ mod $m$ satisfy the Erd\H{o}s-P\'osa property if $m=2$ or $m=4$, but not if $m > 4$ is composite. We show that if $p$ is prime, then $A$-paths of length $0$ mod $p$ satisfy the Erd\H{o}s-P\'osa property. More
Externí odkaz:
http://arxiv.org/abs/2009.12230
Autor:
Thomas, Robin, Yoo, Youngho
Publikováno v:
J. Combin. Theory Ser. B 161 (2023), 228-267
We prove a refinement of the flat wall theorem of Robertson and Seymour to undirected group-labelled graphs $(G,\gamma)$ where $\gamma$ assigns to each edge of an undirected graph $G$ an element of an abelian group $\Gamma$. As a consequence, we prov
Externí odkaz:
http://arxiv.org/abs/2009.11266
Autor:
Thomas, Robin, Yoo, Youngho
Publikováno v:
In Journal of Combinatorial Theory, Series B July 2023 161:228-267
Autor:
Thomas, Robin, Yoo, Youngho
Publikováno v:
In Journal of Combinatorial Theory, Series B May 2023 160:114-143