A051106 Second diagonal of triangle A048601.

1, 3, 14, 105, 1287, 26026, 873392, 48825972, 4559177300, 712438499850, 186574469114250, 81973527087903750, 60475684628083567500, 74966560165861256115000, 156232609877290216839177600

Offset: 2

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Programs

Mathematica

Table[n*(2*n-3)!/(n-2)! * Product[((3*k + 1)!/(n + k)!), {k, 0, n-2}], {n, 2, 20}] (* Vaclav Kotesovec, Oct 26 2017 *)

Formula

a(n) ~ Pi^(1/3) * exp(1/36) * 3^(3*n^2/2 - 3*n + 47/36) * n^(31/36) / (A^(1/3) * Gamma(1/3)^(2/3) * 2^(2*n^2 - 4*n + 31/12)), where A is the Glaisher-Kinkelin constant A074962. - Vaclav Kotesovec, Oct 26 2017

Extensions

More terms from James Sellers