A144888 Second column (m=2) of triangle A144886 (S1hat(4)).

1, 4, 36, 200, 1720, 12480, 118560, 1081920, 11793600, 131443200, 1658764800, 21990528000, 319711795200, 4922394624000, 81508654080000, 1428114530304000, 26582538673152000, 521466739605504000, 10779099461222400000, 233753593186713600000, 5310546788872765440000

Offset: 0

Author

Wolfdieter Lang, Oct 09 2008

Keywords

• nonn
• easy

Crossrefs

Cf. A144886, A001715 (first column), A144889 (third column).

Formula

a(n) = A144886(n+2,2), n>=0.