%I #6 Jan 31 2016 09:39:25
%S 1,0,-12,-120,4368,327360,-762432,-2379861120,-176278202112,
%T 34929443235840,10554181240931328,-234919154252175360,
%U -852275452306594394112,-157606057918154970808320
%N sech(tan(x)*sin(x))=1-12/4!*x^4-120/6!*x^6+4368/8!*x^8...
%t With[{nn=30},Take[CoefficientList[Series[Sech[Tan[x]Sin[x]],{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Jan 31 2016 *)
%K sign
%O 0,3
%A Patrick Demichel (patrick.demichel(AT)hp.com)