Results 41 to 50 of about 168,763 (311)

The complexity of two graph orientation problems

open access: yes, 2012
This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2012 ElsevierWe consider two orientation problems in a graph, namely the minimization of the sum of all the shortest path ...
Noble, Steven D.   +7 more
core   +1 more source

Coloring graphs with forbidden minors

open access: yesJournal of Combinatorial Theory, Series B, 2017
Hadwiger's conjecture from 1943 states that for every integer $t\ge1$, every graph either can be $t$-colored or has a subgraph that can be contracted to the complete graph on $t+1$ vertices. As pointed out by Paul Seymour in his recent survey on Hadwiger's conjecture, proving that graphs with no $K_7$ minor are $6$-colorable is the first case of ...
Martin Rolek, Zi-Xia Song
openaire   +4 more sources

Minimizing the oriented diameter of a planar graph

open access: yes, 2009
We consider the problem of minimizing the diameter of an orientation of a planar graph. A result of Chvátal and Thomassen shows that for general graphs, it is NP-complete to decide whether a graph can be oriented so that its diameter is at most two.
Noble, SD   +3 more
core   +1 more source

Grid Minors of Graphs on the Torus

open access: yesJournal of Combinatorial Theory, Series B, 1994
The face-width of a graph embedded on the torus is the smallest \(n\) such that there is a noncontractible cycle on the torus which intersects the graph in exactly \(n\) points. For example, the product of two \(n\)-cycles \(C_ n\times C_ n\) embeds on the torus with face-width \(n\); this embedding is called the toroidal \(n\)-grid. A graph \(H\) is a
de Graaf, M., Schrijver, A.
openaire   +4 more sources

Graphs with no $\bar P_7$-Minor [PDF]

open access: yesThe Electronic Journal of Combinatorics, 2016
Let $\bar P_7$ denote the complement of a path on seven vertices. We determine all 4-connected graphs that do not contain $\bar P_7$ as a minor.
Guoli Ding   +2 more
openaire   +2 more sources

The Liouville and the intersection properties are equivalent for planar graphs [PDF]

open access: yes, 2012
It is shown that if a planar graph admits no non-constant bounded harmonic function then the trajectories of two independent simple random walks intersect almost ...
Itai Benjamini   +5 more
core   +1 more source

Clique Minors in Graphs and Their Complements

open access: yesJournal of Combinatorial Theory, Series B, 2000
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Bruce A. Reed, Robin Thomas 0001
openaire   +1 more source

Every infinitely edge-connected graph contains the Farey graph or Tℵ0 ∗ t as a minor [PDF]

open access: yes, 2022
We show that every infinitely edge-connected graph contains the Farey graph or Tℵ0 ∗ t as a minor.
Kurkofka, Jan
core   +1 more source

Faster parameterized algorithms for modification problems to minor-closed classes [PDF]

open access: yesTheoretiCS
Let ${\cal G}$ be a minor-closed graph class and let $G$ be an $n$-vertex graph. We say that $G$ is a $k$-apex of ${\cal G}$ if $G$ contains a set $S$ of at most $k$ vertices such that $G\setminus S$ belongs to ${\cal G}$.
Laure Morelle   +3 more
doaj   +1 more source

Rectilinear Crossing Number of Graphs Excluding a Single-Crossing Graph as a Minor [PDF]

open access: yes
The rectilinear crossing number of G is the minimum number of crossings in a straight-line drawing of G. A single-crossing graph is a graph whose crossing number is at most one.
Dujmović, Vida, La Rose, Camille
core   +1 more source

Home - About - Disclaimer - Privacy