This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A035077 #11 Jul 08 2025 21:30:09
%S A035077 1,6,15,70,105,2310,5005,30030,255255,3233230,969969,44618574,
%T A035077 37182145,223092870,3234846615,66853496710,100280245065,200560490130,
%U A035077 1236789689135,7420738134810,30425026352721
%N A035077 Denominators of partial sums of Bernoulli numbers B_{2n} = A000367/A002445.
%H A035077 <a href="/index/Be#Bernoulli">Index entries for sequences related to Bernoulli numbers.</a>
%t A035077 Denominator[Accumulate[BernoulliB[2*Range[0,20]]]] (* _Harvey P. Dale_, May 24 2015 *)
%Y A035077 Cf. A035078.
%K A035077 nonn,easy,frac
%O A035077 0,2
%A A035077 _N. J. A. Sloane_