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%I #13 Dec 26 2016 05:09:27
%S 1,1,2,3,24,60,720,2520,40320,25920,3628800,19958400,479001600,
%T 3113510400,87178291200,653837184000,2988969984000,1243662336000,
%U 6402373705728000,5529322745856000,143111882833920000,115590366904320000,1124000727777607680000
%N Denominators of coefficients in expansion of exp(x)/(1 - x - x^2).
%C a(n) is the denominator of Sum_{k=0..n} A000045(n-k)/k!. - _Robert Israel_, Dec 26 2016
%H Clark Kimberling, <a href="/A279335/b279335.txt">Table of n, a(n) for n = 0..1000</a>
%e (1/1) + (2/1)x + (7/2)x^2 + (17/3)x^3 + (221/24)x^4 ... ; 1/1, 2/1, 7/2, 17/3, ... = A279334/A279335.
%p S:= series(exp(x)/(1-x-x^2),x,101):
%p seq(denom(coeff(S,x,j)),j=0..100); # _Robert Israel_, Dec 26 2016
%t z = 30; t = CoefficientList[Series[E^x/(1 - x - x^2), {x, 0, z}], x];
%t Numerator[t] (* A279334 *)
%t Denominator[t] (* A279335 *)
%Y Cf. A000045, A279334.
%K nonn,easy,frac
%O 0,3
%A _Clark Kimberling_, Dec 12 2016