Enumeration of Switching Non-isomorphic Signed Wheels

TL;DR

This paper counts and generates switching non-isomorphic signed wheel graphs with various negative edge configurations, providing explicit counts for small wheel sizes.

Contribution

It introduces a method to compute and generate switching non-isomorphic signed wheels for specific negative edge counts and small wheel sizes.

Findings

Computed  values of _{p}(n) for specified p and n

Determined (n) for n=4 to 10

Developed a method to count and generate these graphs

Abstract

Two signed graphs are called switching isomorphic to each other if one is isomorphic to a switching of the other. The wheel $W_n$ is the join of the cycle $C_n$ and a vertex. For $0 \leq p \leq n$, $\psi_{p}(n)$ is defined to be the number of switching non-isomorphic signed $W_n$ with exactly $p$ negative edges on $C_n$. The number of switching non-isomorphic signed $W_n$ is denoted by $\psi(n)$. In this paper, we compute the values of $\psi_{p}(n)$ for $p=0,1,2,3,4,n-4,n-3,n-2,n-1,n$ and of $\psi(n)$ for $n=4,5,...,10$. Our method of obtaining $\psi_{p}(n)$ not only count the switching non-isomorphic signed wheels but also generates them.