%I #4 Feb 24 2012 12:51:09
%S 1,-1,-3,-45,2457,-36825,12566037,-1732392389,313988548273,
%T -92368244011185,30231378922437805,-12317648529216417629,
%U 6168347852710380187977,-3616136826996686827399305
%N sech(sec(x)*arcsinh(x))=1-1/2!*x^2-3/4!*x^4-45/6!*x^6+2457/8!*x^8...
%K sign
%O 0,3
%A Patrick Demichel (patrick.demichel(AT)hp.com)