A012503 - OEIS

%I #6 Jan 21 2014 11:44:25

%S 1,-6,108,-5880,624848,-110121440,29157594048,-10831610048896,

%T 5375188617697536,-3434391975840699904,2745651126153216330752,

%U -2684651090523817558325248,3151501790727433916335149056

%N arcsinh(cos(x)*arctan(x))=x-6/3!*x^3+108/5!*x^5-5880/7!*x^7...

%t With[{nn=30},Take[CoefficientList[Series[ArcSinh[Cos[x]ArcTan[x]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Jan 21 2014 *)

%K sign

%O 0,2

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