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 A096456 #16 Oct 13 2020 23:37:23
%S A096456 1,2,3,11,344,355,51819,52174,260515,573204,4846147,5419351,37362253,
%T A096456 42781604,122925461,411557987,534483448,2549491779,3083975227,
%U A096456 17969367914,21053343141,881156436695,902209779836,2685575996367
%N A096456 Numerators of convergents to Pi/2.
%H A096456 M. F. Hasler, <a href="/A096456/b096456.txt">Table of n, a(n) for n = 1..1500</a>, Oct 13 2020
%H A096456 I. Rosenholtz, <a href="http://www.jstor.org/stable/2690793">Tangent sequences, world records, ...</a>, Math. Mag., 72 (No. 5, 1999), 367-376.
%e A096456 1, 2, 3/2, 11/7, 344/219, 355/226, ...
%t A096456 Table[Numerator[FromContinuedFraction[ContinuedFraction[Pi/2, n]]], {n, 1, 25}] (* _Stefan Steinerberger_, Mar 18 2006 *)
%o A096456 (PARI) contfracpnqn(c=contfrac(Pi/2),#c)[1,] \\ _M. F. Hasler_, Oct 13 2020
%Y A096456 Cf. A096463 (denominators), A053300.
%Y A096456 Cf. A002485 (numerators of convergents to Pi).
%K A096456 nonn,frac,easy
%O A096456 1,2
%A A096456 _N. J. A. Sloane_, Aug 16 2004
%E A096456 More terms from _Stefan Steinerberger_, Mar 18 2006