a(n) = n*A029767(n-1).

Terms

a(0) =0a(1) =0a(2) =2a(3) =9a(4) =56a(5) =450a(6) =4464a(7) =52920a(8) =731520a(9) =11566800a(10) =206035200a(11) =4083488640a(12) =89137843200