A091137(n) / A001316(n) .

Terms

a(0) =1a(1) =1a(2) =6a(3) =6a(4) =360a(5) =360a(6) =15120a(7) =15120a(8) =1814400a(9) =1814400a(10) =119750400a(11) =119750400a(12) =653837184000a(13) =653837184000