A012370 - OEIS

%I #6 Mar 06 2019 11:27:36

%S 2,4,-58,-1976,116042,17175244,-594271858,-470273780336,

%T -11672416091758,34320709687067284,5944386529990688342,

%U -5070047337737884665896,-2469435785086687214539558

%N arcsinh(tan(x)*sin(x))=2/2!*x^2+4/4!*x^4-58/6!*x^6-1976/8!*x^8...

%t With[{nn=30},Take[CoefficientList[Series[ArcSinh[Tan[x]Sin[x]],{x,0,nn}],x] Range[0,nn]!,{3,-1,2}]] (* _Harvey P. Dale_, Mar 06 2019 *)

%K sign

%O 0,1

%A Patrick Demichel (patrick.demichel(AT)hp.com)