%I #4 Feb 24 2012 12:50:37
%S 1,-1,5,-13,-407,30151,-1142483,19202427,3747342929,-722092683505,
%T 76341208430549,-2313301317273981,-1769780901329435719,
%U 628518840135423728599,-125498832189487922441219
%N sech(sin(sinh(x)))=1-1/2!*x^2+5/4!*x^4-13/6!*x^6-407/8!*x^8...
%K sign
%O 0,3
%A Patrick Demichel (patrick.demichel(AT)hp.com)