A012446 - OEIS

%I #6 Nov 05 2013 10:28:29

%S 2,0,280,-2688,1016608,-44971520,22528934272,-2475890192384,

%T 1731096311210496,-365422134993502208,343466758613102303232,

%U -121096429560806448922624,146997236520941470929985536

%N arcsin(arctan(x)*tan(x))=2/2!*x^2+280/6!*x^6-2688/8!*x^8+1016608/10!*x^10...

%t With[{nn=30},Take[CoefficientList[Series[ArcSin[ArcTan[x]Tan[x]],{x,0,nn}],x] Range[0,nn]!,{3,-1,2}]] (* _Harvey P. Dale_, Nov 05 2013 *)

%K sign

%O 0,1

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