Forbidden subgraphs for collapsible graphs and supereulerian graphs
نویسندگان
چکیده
منابع مشابه
Pairs of forbidden subgraphs and 2-connected supereulerian graphs
Let G be a 2-connected claw-free graph. We show that • if G is N1,1,4-free or N1,2,2-free or Z5-free or P8-free, respectively, then G has a spanning eulerian subgraph (i.e. a spanning connected even subgraph) or its closure is the line graph of a graph in a family of well-defined graphs, • if the minimum degree δ(G) ≥ 3 and G is N2,2,5-free or Z9-free, respectively, then G has a spanning euleri...
متن کاملSupereulerian graphs with width s and s-collapsible graphs
For an integer s > 0 and for u, v ∈ V (G) with u ≠ v, an (s; u, v)-trail-system of G is a subgraphH consisting of s edge-disjoint (u, v)-trails. A graph is supereulerianwithwidth s if for any u, v ∈ V (G) with u ≠ v, G has a spanning (s; u, v)-trail-system. The supereulerian width μ(G) of a graph G is the largest integer s such that G is supereulerian with width k for every integer kwith 0 ≤ k ...
متن کاملGraphs with Forbidden Subgraphs
Many graphs which are encountered in the study of graph theory are characterized by a type of configuration or subgraph they possess. However, there are occasions when such graphs are more easily defined or described by the kind of subgraphs they are not permitted to contain. For example, a tree can be defined as a connected graph which contains no cycles, and Kuratowski [22] characterized plan...
متن کاملUniversal Graphs (with Forbidden Subgraphs)
The graph theoretic problem of identifying the finite sets C of constraint graphs for which there is a countable universal C-free graph is closely related to the problem of determining for which sets C the model companion T ∗ C of the theory of C-free graphs is א0-categorical, and this leads back to combinatorics. Little is known about these theories from any other perspective, such as stabilit...
متن کاملForbidden subgraphs in connected graphs
Given a set ξ = {H1,H2, · · ·} of connected non acyclic graphs, a ξ-free graph is one which does not contain any member of ξ as copy. Define the excess of a graph as the difference between its number of edges and its number of vertices. Let Ŵk,ξ be theexponential generating function (EGF for brief) of connected ξ-free graphs of excess equal to k (k ≥ 1). For each fixed ξ, a fundamental differen...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Discussiones Mathematicae Graph Theory
سال: 2019
ISSN: 1234-3099,2083-5892
DOI: 10.7151/dmgt.2270