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 A172274 #11 Sep 08 2022 08:45:50
%S A172274 0,0,0,0,1,1,1,2,2,2,2,3,3,3,4,4,4,4,5,5,5,6,6,6,6,7,7,7,8,8,8,8,9,9,
%T A172274 9,10,10,10,10,11,11,11,12,12,12,13,13,13,13,14,14,14,15,15,15,15,16,
%U A172274 16,16,17,17,17,17,18,18,18,19,19,19,19,20,20,20,21,21,21,21,22,22,22,23
%N A172274 a(n) = floor(n*(sqrt(13)-sqrt(11))).
%H A172274 Vincenzo Librandi, <a href="/A172274/b172274.txt">Table of n, a(n) for n = 0..1000</a>
%F A172274 a(n) = floor(n*(A010470 - A010468)). - _Rick L. Shepherd_, Jun 17 2010
%t A172274 With[{c = Sqrt[13] - Sqrt[11]}, Floor[c Range[0, 80]]] (* _Vincenzo Librandi_, Aug 01 2013 *)
%o A172274 (Magma) [Floor(n*(Sqrt(13)-Sqrt(11))): n in [0..80]]; // _Vincenzo Librandi_, Aug 01 2013
%Y A172274 Cf. A010470, A010468, A172264, A172266-A172270, A172272-A172278.
%K A172274 nonn,easy
%O A172274 0,8
%A A172274 _Vincenzo Librandi_, Jan 30 2010
%E A172274 Edited by _Rick L. Shepherd_, Jun 17 2010