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A374333 a(n) is the denominator of x(n) = (2*x(n-1) + 1/n) mod 1, with x(0) = 0.

%I A374333 #25 Jul 14 2024 15:41:59
%S A374333 1,1,2,3,12,30,30,105,840,1260,63,693,2772,18018,18018,45045,720720,
%T A374333 6126120,3063060,29099070,58198140,29099070,29099070,334639305,
%U A374333 2677114440,6692786100,1673196525,5019589575,20078358300,291136195350,291136195350,4512611027925,144403552893600
%N A374333 a(n) is the denominator of x(n) = (2*x(n-1) + 1/n) mod 1, with x(0) = 0.
%C A374333 See A374332 for details and links.
%H A374333 Paolo Xausa, <a href="/A374333/b374333.txt">Table of n, a(n) for n = 0..2000</a>
%t A374333 Block[{n = 0}, Denominator[NestList[Mod[2*# + 1/++n, 1] &, 0, 50]]]
%o A374333 (Python)
%o A374333 from itertools import count, islice
%o A374333 from fractions import Fraction
%o A374333 def A374333_gen(): # generator of terms
%o A374333     a = Fraction(0,1)
%o A374333     for n in count(1):
%o A374333         yield a.denominator
%o A374333         a = (2*a+Fraction(1,n)) % 1
%o A374333 A374333_list = list(islice(A374333_gen(),20)) # _Chai Wah Wu_, Jul 13 2024
%o A374333 (PARI) x(n) = if (n==0, 0, 2*x(n-1) + 1/n);
%o A374333 a(n) = denominator(frac(x(n))); \\ _Michel Marcus_, Jul 13 2024
%Y A374333 Cf. A374332 (numerators), A374335.
%K A374333 nonn,frac
%O A374333 0,3
%A A374333 _Paolo Xausa_, Jul 06 2024