It is proven that every connected Cayley graph X , of valency at least three, on a Hamiltonian group is either Hamilton laceable when X is bipartite, or Hamilton connected when X is not bipartite.
Group connectivity of complementary graphs
✍ Scribed by Xinmin Hou; Hong-Jian Lai; Ping Li; Cun-Quan Zhang
- Publisher
- John Wiley and Sons
- Year
- 2011
- Tongue
- English
- Weight
- 113 KB
- Volume
- 69
- Category
- Article
- ISSN
- 0364-9024
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✦ Synopsis
Abstract
Let G be a 2‐edge‐connected undirected graph, A be an (additive) abelian group and A* = A−{0}. A graph G is A‐connected if G has an orientation D(G) such that for every function b: V(G)↦A satisfying , there is a function f: E(G)↦A* such that for each vertex v∈V(G), the total amount of f values on the edges directed out from v minus the total amount of f values on the edges directed into v equals b(v). For a 2‐edge‐connected graph G, define Λ~g~(G) = min{k: for any abelian group A with |A|⩾k, G is A‐connected }. In this article, we prove the following Ramsey type results on group connectivity:
Let G be a simple graph on n⩾6 vertices. If min{δ(G), δ(G^c^)}⩾2, then either Λ~g~(G)⩽4, or Λ~g~(G^c^)⩽4.
Let Z~3~ denote the cyclic group of order 3, and G be a simple graph on n⩾44 vertices. If min{δ(G), δ(G^c^)}⩾4, then either G is Z~3~‐connected, or G^c^ is Z~3~‐connected. © 2011 Wiley Periodicals, Inc. J Graph Theory
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