%I #12 Jan 27 2014 09:13:00
%S 1,3,17,371,11329,398211,31717649,2487281075,257775723265,
%T 40422383525763,6249491749613201,1324448178268807283,
%U 327217658581539104833,91010297536273890164739,29953128179590939779490961,11561544419017955546723388851
%N Expansion of tan(tanh(x))/cos(x).
%t With[{nn=30},Take[CoefficientList[Series[Tan[Tanh[x]]/Cos[x],{x,0,nn}],x]Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Oct 08 2012 *)
%K nonn
%O 0,2
%A _R. H. Hardin_
%E Extended and signs tested Mar 15 1997 by _Olivier GĂ©rard_.
%E More terms from _Harvey P. Dale_, Oct 08 2012