Multiply successively by 1,1,2,2,3,3,4,4,..., n >= 1, a(0) = 1.

A010551

Multiply successively by 1,1,2,2,3,3,4,4,..., n >= 1, a(0) = 1.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =12a(6) =36a(7) =144a(8) =576a(9) =2880a(10) =14400a(11) =86400a(12) =518400a(13) =3628800a(14) =25401600a(15) =203212800a(16) =1625702400a(17) =14631321600a(18) =131681894400

External references