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%I #10 Jun 01 2021 12:42:08
%S 1,3,33,739,26913,1416995,101493889,9507242819,1129063338945,
%T 165774337045955,29468302949572705,6227421783562843427,
%U 1539946012373786340321,439696998663601508079587
%N Expansion of tan(tan(sin(x))).
%t With[{nn=30},Take[CoefficientList[Series[Tan[Tan[Sin[x]]],{x,0,nn}],x] Range[ 0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Jun 01 2021 *)
%K nonn
%O 0,2
%A _R. H. Hardin_
%E Extended and signs tested Mar 15 1997 by _Olivier Gérard_.
%E Prior Mathematica program replaced by _Harvey P. Dale_, Jun 01 2021