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 A053431 #23 Dec 23 2021 21:50:59 %S A053431 78256779,340262731,1963319607,13402974518,26805949036,40208923554, %T A053431 5703436923116,136308121570117,272616243140234,1684937174853026414, %U A053431 3369874349706052828,5054811524559079242,75474011359728834791267,909474452321624805685313,1818948904643249611370626 %N A053431 Numbers k such that (Pi/2)*k^2*sin(1/k) < floor(Pi*k/2). %C A053431 The solution uses sequence A001203, the continued fraction expansion of Pi. - _T. D. Noe_, Mar 13 2014 %H A053431 Michael A. Filaseta, Allen Stenger, D. Callan and Z. Franco, <a href="http://www.jstor.org/stable/2589451">Solution to Problem 10640: When a Multiple of Pi/2 is Close to an Integer</a>, Amer. Math. Monthly, 107 (2000), 177-178. %Y A053431 Cf. A001203. %K A053431 nonn %O A053431 1,1 %A A053431 _N. J. A. Sloane_, Mar 21 2000 %E A053431 More terms from Antreas P. Hatzipolakis (xpolakis(AT)otenet.gr), May 25 2000 %E A053431 Better name from _T. D. Noe_, Mar 13 2014 %E A053431 More terms from _Sean A. Irvine_, Dec 23 2021