A NOTE ON PRIME LABELING OF LADDERS

摘要

A bijective labeling on the vertex set V of a simple, finiterngraph G with labels from {1, 2, ………|V|} is called a primernlabeling if any two adjacent vertices of G receive co-prime labels. It has been conjectured that ladders [3] are prime. A few cases of ladders have been proved prime in literature [1] and we enlarge this list.