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 A140814 #20 Sep 08 2022 08:45:34
%S A140814 3,6,30,42,30,66,2730,6,510,798,330,138,2730,6,870,14322,510,6,
%T A140814 1919190,6,13530,1806,690,282,46410,66,1590,798,870,354,56786730,6,
%U A140814 510,64722,30,4686,140100870,6,30,3318,230010,498,3404310,6,61410,272118,1410,6
%N A140814 a(0)=3, a(n)=A002445(n) for n >= 1.
%H A140814 Vincenzo Librandi, <a href="/A140814/b140814.txt">Table of n, a(n) for n = 0..1000</a>
%F A140814 a(n) = A106458(2*n) + A106458(2*n+1).
%F A140814 a(n) = A027762(n) for n >= 1. - _Georg Fischer_, Nov 03 2018
%t A140814 Join[{3}, Table[Denominator[BernoulliB[2 n]], {n, 60}]] (* _Vincenzo Librandi_, Nov 04 2018 *)
%o A140814 (Magma) [3] cat [Denominator(Bernoulli(2*n)): n in [1..60]]; // _Vincenzo Librandi_, Nov 04 2018
%Y A140814 Cf. A027762, A140816.
%K A140814 nonn,less
%O A140814 0,1
%A A140814 _Paul Curtz_, Jul 16 2008
%E A140814 Edited and extended by _R. J. Mathar_, Jul 29 2008