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%I #4 Feb 24 2012 12:50:40
%S 1,2,24,888,68352,8853888,1724221056,470304668928,171029448056832,
%T 79950698284462080,46709069479002931200,33347332565041919950848,
%U 28565775294718770340331520,28915860353300526164581613568
%N arcsinh(arcsin(tan(x)))=x+2/3!*x^3+24/5!*x^5+888/7!*x^7+68352/9!*x^9...
%K nonn
%O 0,2
%A Patrick Demichel (patrick.demichel(AT)hp.com)