%I #11 Jan 23 2015 14:33:31
%S 0,1,2,7,20,117,518,4555,27432,317577,2405194,34316335,312554428,
%T 5287957053,56240197198,1099518892339,13369846932560,296443784525713,
%U 4056020122211730,100546719214082775,1528702557462347620
%N Expansion of tan(tan(x))*exp(x).
%F a(n) ~ n! * 4 * ((-1)^(n+1) + exp(2*arctan(Pi/2))) /((4+Pi^2) * exp(arctan(Pi/2)) * arctan(Pi/2)^(n+1)). - _Vaclav Kotesovec_, Jan 23 2015
%t Tan[ Tan[ x ] ]*Exp[ x ]
%t CoefficientList[Series[E^x*Tan[Tan[x]], {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Jan 23 2015 *)
%K nonn,easy
%O 0,3
%A _R. H. Hardin_
%E Extended and signs tested Mar 15 1997 by _Olivier GĂ©rard_.