A024271 - OEIS

%I #12 May 28 2012 14:15:11

%S 0,1,6,59,940,31637,2005106,166100111,16050083800,1874971666857,

%T 279670143989598,53041020901061987,12139626880904714372,

%U 3219275040968635076157,979189869389394861709514,342690421890075448877502135,137691551060667051544057815472

%N E.g.f. tan(x)*tan(sin(x))/2, even powers only.

%t With[{nn=40},Take[CoefficientList[Series[Tan[x] Tan[Sin[x]]/2,{x,0,nn}], x]Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, May 28 2012 *)

%Y A009748.

%K nonn

%O 0,3

%A _R. H. Hardin_

%E Extended and signs tested 03/97.

%E More terms from and definition clarified by _Harvey P. Dale_, May 28 2012