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%I #15 May 01 2023 10:03:15
%S 1,4,36,1,3600,1,211680,1,10886400,1,526901760,1,16999766784000,1,
%T 1120863744000,1,181400588328960000,1,97072790126247936000,1,
%U 16860010916664115200000,1,324325300906011525120000,1
%N Denominators of expansion for Debye function for n=1: D(1,x).
%C Numerators are found under A120082.
%H G. C. Greubel, <a href="/A120083/b120083.txt">Table of n, a(n) for n = 0..447</a>
%F a(n) = denominator(r(n)), with r(n) = [x^n]( 1 - x/4 + Sum_{k >= 0}(B(2*k)/((2*k+1)*(2*k)!))*x^(2*k) ), |x|<2*pi. B(2*k) = A000367(k)/A002445(k) (Bernoulli numbers).
%F a(n) = denominator(B(n)/(n+1)!), n >= 0. See the comment on the e.g.f. D(1,x) in A120082. - _Wolfdieter Lang_, Jul 15 2013
%t Table[Denominator[BernoulliB[n]/(n+1)!], {n,0,50}] (* _G. C. Greubel_, May 01 2023 *)
%o (Magma) [Denominator(Bernoulli(n)/Factorial(n+1)): n in [0..50]]; // _G. C. Greubel_, May 01 2023
%o (SageMath)
%o def A120083(n): return denominator(bernoulli(n)/factorial(n+1))
%o [A120083(n) for n in range(51)] # _G. C. Greubel_, May 01 2023
%Y Cf. A120082.
%K nonn,easy,frac
%O 0,2
%A _Wolfdieter Lang_, Jul 20 2006