A Spanning Union of Cycles in Thin Cylinder, Torus and Klein Bottle Grid Graphs

Abstract

In this paper, we propose an algorithm for obtaining the common transfer digraph Dm* for enumeration of 2-factors in graphs from the title, all of which have m·n vertices (m,n∈N,m≥2). The numerical data gathered for m≤18 reveal some matches for the numbers of 2-factors for different types of torus or Klein bottle. In the latter case, we conjecture that these numbers are invariant under twisting.

Keywords

• generating functions
• enumerations
• combinatorial counting