A144272 - OEIS

%I #6 Jul 02 2023 06:07:25

%S 1,1,4,18,129,1095,11880,149940,2218545,37147005,699281100,

%T 14561835750,332913128625,8280095098275,222659485448400,

%U 6434896997529000,198909798356894625,6547761582390653625,228681849947367316500,8445341134525197152250,328822530412023653630625

%N Second column (m=2) of triangle S2hat(-1) = A144270.

%F a(n) = A144270(n+2,2), n>=0.

%Y Cf. A144270.

%Y Cf. A001147 (column m=1), A144273 (column m=3).

%K nonn,easy

%O 0,3

%A _Wolfdieter Lang_, Oct 09 2008