Decomposing Complete Graphs into Isomorphic Subgraphs with Six Vertices and Seven Edges

Zihong Tian1, Yanke Du2, Qingde Kang1
1Institute of Math., Hebei Normal University, Shijiazhuang 050016, P. R. China
2Dept. of Basic Courses, Ordnance Engineering College, Shijiazhuang 050003, P. R. China

Abstract

Let \(K_v\) be the complete multigraph with \(v\) vertices. Let \(G\) be a finite simple graph. A \(G\)-design of \(K_v\), denoted by \(G\)-GD(\(v\)), is a pair of (\(X\), \(\mathcal{B}\)), where \(X\) is the vertex set of \(K_v\), and \(\mathcal{B}\) is a collection of subgraphs of \(K_v\), called blocks, such that each block is isomorphic to \(G\) and any two distinct vertices in \(K_v\) are joined in exactly one block of \(\mathcal{B}\). In this paper, the discussed graphs are sixteen graphs with six vertices and seven edges. We give a unified method for constructing such \(G\)-designs.