Prime Labeling of Ladders

Abstract

A prime labeling of a graph with $n$ vertices is a labeling of its vertices with distinct integers from $\{1,2,\dots ,n\}$ in such a way that the labels of any two adjacent vertices are relatively prime. T. Varkey conjectured that ladder graphs have a prime labeling. We prove this conjecture.

Cited by in corpus (1)

• Minimum coprime graph labelings