%I #7 Feb 24 2012 12:51:04
%S 2,-128,12032,365688832,-2002811158528,-67148259011330048,
%T 3766780331499896963072,40680896591210190242578432,
%U -72225295511520670153244114157568
%N Expansion of tanh(tanh(x)*tan(x)).
%e tanh(tanh(x)*tan(x))=2/2!*x^2-128/6!*x^6+12032/10!*x^10...
%t Tanh[ Tanh[ x ]*Tan[ x ] ] (* [ x^(4n+2) ] *)
%Y 2 * A009823(n).
%K sign
%O 0,1
%A Patrick Demichel (patrick.demichel(AT)hp.com)