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A013526 Numerator of [x^(2n)] of the Taylor expansion cosh(cosec(x)-cot(x))=1 +x^2/8 +3*x^4/128 +59*x^6/15360 +871*x^8/1474560 +.... 1

%I

%S 1,1,3,59,871,325249,35797,24362249,342232522657,8224154352439,

%T 23157229065769,9926476934520521,37638416003805990839,

%U 296699416391356495667713,691054566545631371393

%N Numerator of [x^(2n)] of the Taylor expansion cosh(cosec(x)-cot(x))=1 +x^2/8 +3*x^4/128 +59*x^6/15360 +871*x^8/1474560 +....

%C The coefficients of the e.g.f. of x/2, cosh(cosec(x)-cot(x)) = 1 + 1*x^2/(2^2*2!) + 9*x^4/(2^4*4!) + 177*x^6/(2^6*6!) + 6097*x^8/(2^8*8!) + ..., are apparently the absolute values of A003711.

%H Vincenzo Librandi, <a href="/A013526/b013526.txt">Table of n, a(n) for n = 0..100</a>

%t Numerator[Take[CoefficientList[Series[Cosh[Csc[x] - Cot[x]], {x, 0, 35}], x], {1, -2, 2}]] (* _Vincenzo Librandi_, Nov 12 2016 *)

%K nonn,frac

%O 0,3

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

%E Name edited by _R. J. Mathar_, Dec 19 2011

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Last modified April 18 04:49 EDT 2021. Contains 343072 sequences. (Running on oeis4.)