Edge even graceful labelling of new families of graphs
Salama Nagy Daoud, Ahmed Noubi Elsawy · Journal of Taibah University for Science · 2019
Elsonbaty and Daoud introduced a new type of labelling of a graph G with p vertices and q edges called an edge even graceful labelling. A graph G is called edge even graceful if there is a bijection f:E(G)→{2,4,…,2q} such that, when each vertex is assigned the sum of all edges incident to it mod 2k, where k=max(p,q), the resulting vertex labels are distinct. In this paper we proved that double fan graphs, quadrilateral friendship graphs, and butterfly graphs are edge even graceful graphs.