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%I #8 Jan 15 2018 15:01:25
%S 1,-3,57,-2587,217137,-29025587,5664605801,-1519556355275,
%T 536514935904609,-241225069255390307,134580033555427233689,
%U -91237165395466088195963,73877505225687035803070353,-70425423338543411535873624467,78071169657855750497737512497097
%N arctan(arcsin(arctan(x))) = x - 3/3!*x^3 + 57/5!*x^5 - 2587/7!*x^7 + 217137/9!*x^9 - ...
%K sign
%O 0,2
%A Patrick Demichel (patrick.demichel(AT)hp.com)