\(G\)-Decomposition of \(\lambda K_v\) where \(G\) has Six Vertices and Nine Edges

Qingde Kang1, Chunping Ma2, Hongtao Zhao1
1Institute of Mathematics, Hebei Normal University, Shijiazhuang 050016, P. R. China
2Department of Applied Mathematics, North China Electric Power University, Baoding 071003, P. R. China

Abstract

Let \(\lambda K_v\) be the complete multigraph with \(v\) vertices. Let \(G\) be a finite simple graph. A \(G\)-decomposition of \(K_v\), denoted by \(G-GD_\lambda(v)\), is a pair \((X, \mathcal{B})\) 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, nine graphs \(G_i\) with six vertices and nine edges are discussed, and the existence of \(G_i-GD_\lambda(v)\) is given, \(1 \leq i \leq 9\).