A129933 a(n) = (n*(n+1)/2+1)!/n!.

1, 2, 12, 840, 1663200, 174356582400, 1561112121913344000, 1754317855900734514790400000, 341362923889542287855059017400320000000, 15163751542692044063740921044974247390216192000000000, 195932150519417838363658963697014150610807423633478962380800000000000

Offset

0,2

Links

Table of n, a(n) for n=0..10.

Mathematica

Table[(n (n+1)/2+1)!/n!, {n, 0, 20}] (* Harvey P. Dale, Aug 04 2022 *)

Crossrefs

Cf. A000124, A107868, A129893.

Sequence in context: A061149 A191555 A222207 * A064320 A112373 A058975

Adjacent sequences: A129930 A129931 A129932 * A129934 A129935 A129936

Keyword

nonn

Author

N. J. A. Sloane, Jun 06 2007

Status

approved