Uniquely Bipancyclic Graphs on More than 30 Vertices

Abdollah Khodkar1, Alex L. Peterson2, Christina J. Wahl3, Zach W. Walsh4
1Department of Mathematics University of West Georgia Carrollton, GA 30118
2Berry College Mount Berry, GA 30149
3The State University of New York at Potsdam Potsdam, NY 13676
4Carleton College Northfield, MN 55057

Abstract

A bipartite graph on \(n\) vertices, with \(n\) even, is called uniquely bi-pancyclic (UBPC) if it contains precisely one cycle of length \(2m\) for every \(2 \leq m \leq \frac{n}{2}\). In this note, using computer programs, we show that if \(32 \leq n \leq 56\), and \(n \neq 44\), then there are no UBPC graphs of order \(n\). We also present the six non-isomorphic UBPC graphs of order 44. This improves the recent results on UBPC graphs of order at most 30.

Keywords: pancyclic graphs, uniquely pancyclic graphs, uniquely “Research supported by NSF REU Grant DMS1262838, University of West Georgia