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 A172270 #13 Sep 08 2022 08:45:50
%S A172270 0,1,2,3,4,5,6,7,8,9,10,11,12,14,15,16,17,18,19,20,21,22,23,24,25,27,
%T A172270 28,29,30,31,32,33,34,35,36,37,38,39,41,42,43,44,45,46,47,48,49,50,51,
%U A172270 52,54,55,56,57,58,59,60,61,62,63,64,65,66,68,69,70,71,72,73,74,75,76,77
%N A172270 a(n) = floor(n*(sqrt(11)-sqrt(5))).
%H A172270 Vincenzo Librandi, <a href="/A172270/b172270.txt">Table of n, a(n) for n = 0..1000</a>
%t A172270 With[{c=Sqrt[11]-Sqrt[5]},Floor[c*Range[0,80]]] (* _Harvey P. Dale_, Apr 24 2013 *)
%o A172270 (Magma) [Floor(n*(Sqrt(11)-Sqrt(5))): n in [0..80]]; // _Vincenzo Librandi_, Aug 01 2013
%o A172270 (PARI) a(n) = floor(n*(sqrt(11)-sqrt(5))) \\ _Charles R Greathouse IV_, Jul 01 2016
%Y A172270 Cf. A172264, A172266-A172269, A172272-A172278.
%K A172270 nonn,easy
%O A172270 0,3
%A A172270 _Vincenzo Librandi_, Jan 30 2010
%E A172270 Checked by _Michael B. Porter_, Jun 16 2010