A graph G is called integral if all the eigenvalues of the adjacency matrix A(G) of G are integers. In this paper, the graphs G4(a,b) and G5 (a, b) with 2a + 6b vertices are defined. We give their characteristic polynomials from matrix theory and prove that the (n+2)-regular graphs G4(n,n+2) and G5(n,n+2) are a pair of non-isomorphic connected cospectral integral regular graphs for any positive integer n.
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机译:Radiation-absorption,chemical reaction,Hall and ion slip impacts on magnetohydrodynamic free convective flow over semi-infinite moving absorbent surface