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 A013432 tan(arctanh(x)-arcsin(x)) = 1/3!*x^3 + 15/5!*x^5 + 495/7!*x^7 + 29855/9!*x^9... 1

%I

%S 0,1,15,495,29855,2874375,404150175,78074371375,19828087485375,

%T 6403087440228375,2561659553274989375,1243334307147747189375,

%U 719656795107349242609375,489659786386680109910734375

%N tan(arctanh(x)-arcsin(x)) = 1/3!*x^3 + 15/5!*x^5 + 495/7!*x^7 + 29855/9!*x^9...

%H Vaclav Kotesovec, <a href="/A013432/b013432.txt">Table of n, a(n) for n = 0..223</a>

%t nn = 20; Table[(CoefficientList[Series[-Tan[ArcSin[x] - ArcTanh[x]], {x, 0, 2*nn+1}], x] * Range[0, 2*nn+1]!)[[n]], {n, 2, 2*nn, 2}] (* _Vaclav Kotesovec_, Feb 06 2015 *)

%K nonn

%O 0,3

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

%E a(0)=0 prepended by _Vaclav Kotesovec_, Feb 06 2015

%E Definition modified by _Vaclav Kotesovec_, Feb 06 2015

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Last modified January 25 14:40 EST 2022. Contains 350572 sequences. (Running on oeis4.)