Prime cordial labelling of graphs. (English) Zbl 1108.05081

Summary: Let \(G=(V,E)\) be a simple graph and \(f:V\to\{1,2,\dots,|V|\}\) be a bijection. For each edge \(uv\), assign the label 1 or 0 according as gcd\( (f(u),f(v))=1\) or not. \(f\) is called a prime cordial labelling if \(|e_f(0)-e_t (1)|\leq 1\) where \(e_f(i)\) is the number of edges labeled with \(i\) \((i=0,1)\). We investigate the prime cordial behaviour of some standard graphs and also graphs generated from them.


05C78 Graph labelling (graceful graphs, bandwidth, etc.)