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 A092799 #18 Jun 03 2019 08:03:16
%S A092799 1,3,243,215233605,2849452841966467687734375,
%T A092799 34139907905802495953388390516678108673704867996275424957275390625
%N A092799 Denominator of partial products in an approximation to Pi/2.
%H A092799 J. Guillera and J. Sondow, <a href="https://arxiv.org/abs/math/0506319">Double integrals and infinite products for some classical constants via analytic continuations of Lerch's transcendent</a>, Ramanujan J. 16 (2008) 247-270; arXiv:math/0506319 [math.NT], 2005-2006.
%H A092799 J. Sondow, <a href="https://arxiv.org/abs/math/0401406">A faster product for Pi and a new integral for ln(Pi/2)</a>, arXiv:math/0401406 [math.NT], 2004.
%H A092799 J. Sondow, <a href="http://www.jstor.org/stable/30037575">A faster product for Pi and a new integral for ln(Pi/2)</a>, Amer. Math. Monthly 112 (2005), 729-734 and 113 (2006), 670.
%F A092799 a(n) = Product_{k=1..n+1} A122215(k)^2^(n-k+1). - _Jonathan Sondow_, Sep 13 2006
%F A092799 a(n) = Denominator(Product_{k=1..n+1} (A122216(k)/A122217(k))^2^(n-k+1)). - _Jonathan Sondow_, Sep 13 2006
%e A092799 The first approximations are 2^(1/2), (16/3)^(1/4), (8192/243)^(1/8), (274877906944/215233605)^(1/16).
%o A092799 (PARI) for(m=1, 7, p=1; for(n=1, m, p=p*p*(prod(k=1, ceil(n/2), (2*k)^binomial(n, 2*k-1))/(prod(k=1, floor(n/2)+1, (2*k-1)^binomial(n, 2*k-2))))); print1(denominator(p), ", "))
%Y A092799 Numerators are in A092798.
%Y A092799 Cf. A000246, A001900, A001901, A001902.
%Y A092799 Cf. A122215, A122217.
%K A092799 nonn,easy,frac
%O A092799 1,2
%A A092799 _Ralf Stephan_, Mar 05 2004