Denominator of Sum_{k=0..n} 1/k!.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =24a(5) =60a(6) =720a(7) =252a(8) =40320a(9) =36288a(10) =3628800a(11) =4989600a(12) =95800320a(13) =3113510400a(14) =17435658240a(15) =326918592000