Number of n X n symmetric matrices each of whose rows is a permutation of 1..n.

A035482

Number of n X n symmetric matrices each of whose rows is a permutation of 1..n.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =96a(5) =720a(6) =328320a(7) =31449600a(8) =440952422400

External references