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Graph TheoryChallengeIsomorphism and Subgraphs

Isomorphism and Subgraphs · Challenge problem

The paw graph consists of a triangle on vertices {a,b,c}\{a, b, c\} with one pendant edge from vertex aa to a leaf dd (edges: ab,ac,bc,adab, ac, bc, ad). How many labeled graphs on the vertex set {1,2,3,4}\{1,2,3,4\} are isomorphic to the paw graph?