Fourth column of triangle A067417.

Terms

a(0) =1a(1) =6a(2) =72a(3) =864a(4) =10368a(5) =124416a(6) =1492992a(7) =17915904a(8) =214990848a(9) =2579890176a(10) =30958682112a(11) =371504185344