Discovery of Some New Classes of Graceful Unicyclic Graphs

Jay Bagga 1, Laure Pauline Fotso 2, Max Junior Pambe Biatch3
1Department of Computer Science Ball State University, Muncie, IN 47306, USA
2Department of Computer Science Faculty of Science, University of Yaounde I, Cameroon
3Department of Computer Science Higher Teachers’ Training College, University of Maroua, Cameroon Faculty of Science, University of Yaounde I, Cameroon

Abstract

Graceful graphs were first studied by Rosa [17]. A graceful labeling \(f\) of a graph G is a one-to-one map from the set of vertices of \(G\) to the set {0.1,., |E(G)|}. where for edges \(xy\), the induced edge labels |f(x) – f (y)| form the set {1,2,., |E(G)|, with no label repeated. In this paper, we investigate the set of labels taken by the central vertex of the star in the graph \(K_{1.m-1} \oplus C_n\), for each graceful labeling. We also study gracefulness of certain unicyclic graphs where paths \(P_3, P_2\) are pendant at vertices of the cycle. For these unicyclic graphs, the deletion of any edge of the cycle does not result in a caterpillar.