A024239 - OEIS

%I #15 Apr 02 2017 15:20:54

%S 0,1,2,-89,-2668,60541,12497462,330911491,-136964474008,

%T -21093217440839,2139299892644522,1436807195496088351,

%U 96866149734285315452,-134387439014403900337739,-47862471480153106563898018

%N Expansion of tanh(tan(x)*sin(x))/2.

%H Vincenzo Librandi, <a href="/A024239/b024239.txt">Table of n, a(n) for n = 0..100</a>

%t With[{nn=30},Take[CoefficientList[Series[Tanh[Tan[x]*Sin[x]]/2,{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Jun 05 2013 *)

%Y Cf. A009815.

%K sign

%O 0,3

%A _R. H. Hardin_

%E Extended with signs by _Olivier Gérard_, Mar 15 1997

%E Previous Mathematica program replaced by _Harvey P. Dale_, Jun 05 2013