<P> The Petersen family consists of the seven graphs that can be formed from the Petersen graph by zero or more applications of Δ - Y or Y - Δ transforms . The complete graph K is also in the Petersen family . These graphs form the forbidden minors for linklessly embeddable graphs, graphs that can be embedded into three - dimensional space in such a way that no two cycles in the graph are linked . </P> <P> The Clebsch graph contains many copies of the Petersen graph as induced subgraphs: for each vertex v of the Clebsch graph, the ten non-neighbors of v induce a copy of the Petersen graph . </P>

Find λ(g) when g is a petersen graph