Triple factorial numbers (3*n-2)!!! with leading 1 added.

A007559

Triple factorial numbers (3*n-2)!!! with leading 1 added.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =28a(4) =280a(5) =3640a(6) =58240a(7) =1106560a(8) =24344320a(9) =608608000a(10) =17041024000a(11) =528271744000

External references