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E.g.f. sinh(arctan(sin(x))) odd powers only.
1

%I #22 Jul 11 2018 03:32:34

%S 1,-2,16,-272,256,1758208,-549115904,178127730688,-68157333438464,

%T 31349506823815168,-17274394522483687424,11298666083444901019648,

%U -8681212227186028691062784,7756335594110841587790512128

%N E.g.f. sinh(arctan(sin(x))) odd powers only.

%C Previous name was: sinh(arctan(sin(x))) = x - 2/3!*x^3 + 16/5!*x^5 - 272/7!*x^7 + 256/9!*x^9 + ...

%H G. C. Greubel, <a href="/A012188/b012188.txt">Table of n, a(n) for n = 0..219</a>

%t With[{nn=30},Take[CoefficientList[Series[Sinh[ArcTan[Sin[x]]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Nov 06 2013 *)

%o (PARI) x = 'x + O('x^40); select(x->x, Vec(serlaplace(sinh(atan(sin(x)))))) \\ _Michel Marcus_, Feb 05 2016

%K sign

%O 0,2

%A Patrick Demichel (patrick.demichel(AT)hp.com)

%E New name from _Michel Marcus_, Feb 05 2016

%E Title corrected by _Sean A. Irvine_, Jul 11 2018