a(n) is the permanent of a 2n X 2n antisymmetric Toeplitz matrix M(2n) whose first row consists of a single zero followed by successive positive integers repeated (A004526).

A331491

a(n) is the permanent of a 2n X 2n antisymmetric Toeplitz matrix M(2n) whose first row consists of a single zero followed by successive positive integers repeated (A004526).

Terms

    a(0) =1a(1) =-1a(2) =8a(3) =-965a(4) =301864a(5) =-276973609a(6) =529706205072

External references