Denominator of Cotesian number C(n,0).

Terms

a(0) =1a(1) =2a(2) =6a(3) =8a(4) =90a(5) =288a(6) =840a(7) =17280a(8) =28350a(9) =89600a(10) =598752a(11) =17418240a(12) =63063000a(13) =402361344000a(14) =5003856000a(15) =295206912a(16) =976924698750