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Denominators of rationals with e.g.f. D(3,x), a Debye function.
3

%I #13 Dec 08 2023 23:36:51

%S 1,8,10,1,70,1,126,1,110,1,286,1,13650,1,34,1,3230,1,5586,1,2530,1,

%T 1150,1,24570,1,58,1,8990,1,157542,1,5950,1,74,1,24949470,1,82,1,

%U 193930,1,27090,1,10810,1,4606,1,788970,1,1166,1,29150,1,15162,1

%N Denominators of rationals with e.g.f. D(3,x), a Debye function.

%C See the comments, references and links under A227570.

%F a(n) = denominator(3*B(n)/(n+3)), n >= 0, with the Bernoulli numbers B(n) = A027641(n)/A027642(n).

%F The e.g.f. of the rationals r(3,n) := 3*B(n)/(n+3) is D(3,x) = (3/x^3)*int(t^3/(exp(x) - 1), t=0..x).

%e The rationals r(3,n), n=0..15 are: 1, -3/8, 1/10, 0, -1/70, 0, 1/126, 0, -1/110, 0, 5/286, 0, -691/13650, 0, 7/34, 0.

%t A227571[n_]:=Denominator[3BernoulliB[n]/(n+3)];

%t Array[A227571,100,0] (* _Paolo Xausa_, Dec 08 2023 *)

%Y Cf. A227570, A027641/A027642.

%K nonn,easy,frac

%O 0,2

%A _Wolfdieter Lang_, Jul 16 2013