OFFSET
1,1
LINKS
J. W. L. Glaisher, On a set of coefficients analogous to the Eulerian numbers, Proc. London Math. Soc., 31 (1899), 216-235.
EXAMPLE
10/3, 34, 910, 415826/9, 3786350, 455594594, 226816276970/3, 16546152735874, 4616987879606830, ...
MAPLE
In := proc(n)
1/(exp(x)+exp(-x)+1) ;
coeftayl(%, x=0, 2*n) ;
%*(2*n)!*(-1)^n*3/2 ;
end proc:
Jn := proc(n)
(2^(2*n+1)+2)*In(n) ;
end proc:
A260336 := proc(n)
numer(Jn(n)) ;
end proc: # R. J. Mathar, Aug 02 2015
MATHEMATICA
GI[n_] := SeriesCoefficient[1/(Exp[x]+Exp[-x]+1), {x, 0, 2n}]*(2n)!*(-1)^n*3/2;
GJ[n_] := (2^(2n+1)+2)*GI[n];
a[n_] := Numerator[GJ[n]];
Table[a[n], {n, 1, 14}] (* Jean-François Alcover, Apr 15 2023, after R. J. Mathar *)
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
N. J. A. Sloane, Jul 29 2015
STATUS
approved