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%I #4 Feb 24 2012 12:51:31
%S -4,60,-1384,50520,-1963564,-2440620,24774209456,-7410634833360,
%T 1946918835205676,-504022869697607700,125734569960701153096,
%U -25506896972028634763640,-308739978510619283180284
%N arctan(cos(x)-sech(x))=-4/4!*x^4+60/6!*x^6-1384/8!*x^8+50520/10!*x^10...
%K sign
%O 0,1
%A Patrick Demichel (patrick.demichel(AT)hp.com)