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%I #15 Apr 02 2017 14:45:17
%S 0,1,-2,19,-900,24677,-1112326,106703735,-9757606664,1107210680265,
%T -185352374028298,34591783336998875,-7446994657977107084,
%U 2008734448727225846317,-618914330538196467929358
%N Expansion of tanh(x)*tan(sin(x))/2.
%t With[{nn=40},Take[CoefficientList[Series[Tanh[x]*Tan[Sin[x]]/2,{x,0,nn}], x]Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Apr 27 2012 *)
%Y Cf. A009835.
%K sign
%O 0,3
%A _R. H. Hardin_
%E Extended with signs Mar 1997