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The complete product of annihilatingly unique digraphs. (English) Zbl 1076.05040
Summary: Let G be a digraph with n vertices and let A(G) be its adjacency matrix. A monic polynomial f(x) of degree at most n is called an annihilating polynomial of G if f(A(G))=0. G is said to be annihilatingly unique if it possesses a unique annihilating polynomial. Difans and diwheels are two classes of annihilatingly unique digraphs. In this paper, it is shown that the complete product of difan and diwheel is annihilatingly unique.
MSC:
05C20Directed graphs (digraphs), tournaments
05C50Graphs and linear algebra