A080141 (3^(n-1))*(n!)^2.

1, 12, 324, 15552, 1166400, 125971200, 18517766400, 3555411148800, 863964909158400, 259189472747520000, 94085778607349760000, 40645056358375096320000, 20607043573696173834240000

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..100

Formula

Expression as an n-th moment of a positive function on a positive half-axis, in Maple notation a(n)=int(x^n*2*BesselK(0, 2*sqrt(x)/sqrt(3))/9, x=0..infinity), n=1, 2... . This is a solution of a Stieltjes moment problem.

Mathematica

Table[(3^(n - 1)) (n!)^2, {n, 1, 30}] (* Vincenzo Librandi, Feb 24 2014 *)

Prog

(PARI) a(n) = (3^(n-1))*(n!)^2; \\ Joerg Arndt, Feb 23 2014

Crossrefs

Sequence in context: A239781 A288032 A365280 * A153468 A230817 A298245

Adjacent sequences: A080138 A080139 A080140 * A080142 A080143 A080144

Keyword

nonn

Author

Karol A. Penson, Jan 30 2003

Status

approved