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%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