a(n) = (A000108(n)^2)*(n+1)!.A089835a(n) = (A000108(n)^2)*(n+1)!.Terms a(0) =1a(1) =2a(2) =24a(3) =600a(4) =23520a(5) =1270080a(6) =87816960a(7) =7420533120a(8) =742053312000External referencesoeis: A089835