OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..230
EXAMPLE
G.f. = 1 + (1/3)*x^2 + (1/18)*x^4 + (13/1890)*x^6 + (17/22680)*x^8 + (97/1247400)*x^10 + ...
MAPLE
a:= n-> denom(coeff(series(sinh(x)/sin(x), x, 2*n+2), x, 2*n)):
seq(a(n), n=0..24); # Alois P. Heinz, Feb 01 2022
MATHEMATICA
With[{m=60}, CoefficientList[Series[Sinh[x]/Sin[x], {x, 0, m}], x]][[1 ;; ;; 2]]//Denominator (* G. C. Greubel, Jan 31 2022 *)
PROG
(Magma)
m:=60; R<x>:=PowerSeriesRing(Rationals(), m);
b:= Coefficients(R!( Sinh(x)/Sin(x) ));
[Denominator( b[2*n-1] ): n in [1..Floor((m-2)/2)]]; // G. C. Greubel, Jan 31 2022
(Sage) [denominator( ( sinh(x)/sin(x) ).series(x, 2*n+3).list()[2*n] ) for n in (0..60)] # G. C. Greubel, Jan 31 2022
CROSSREFS
KEYWORD
easy,frac,nonn
AUTHOR
Benoit Cloitre, May 03 2002
STATUS
approved