a(n) is the permanent of the n X n symmetric matrix M(n) defined by M[i, j, n] = min(i, j)*(n + 1) - i*j.

A362679

a(n) is the permanent of the n X n symmetric matrix M(n) defined by M[i, j, n] = min(i, j)*(n + 1) - i*j.

Terms

    a(0) =1a(1) =1a(2) =5a(3) =72a(4) =2309a(5) =140400a(6) =14495641a(7) =2347782144a(8) =562385930985

External references