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 A008604 #58 Mar 02 2025 10:03:54
%S A008604 0,22,44,66,88,110,132,154,176,198,220,242,264,286,308,330,352,374,
%T A008604 396,418,440,462,484,506,528,550,572,594,616,638,660,682,704,726,748,
%U A008604 770,792,814,836,858,880,902,924,946,968,990,1012,1034,1056,1078,1100,1122,1144
%N A008604 Multiples of 22.
%C A008604 Even numbers for which the sum of "digits" base 100 is divisible by 11. - _Daniel Forgues_, Feb 22 2016
%H A008604 Vincenzo Librandi, <a href="/A008604/b008604.txt">Table of n, a(n) for n = 0..1000</a>
%H A008604 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>.
%H A008604 INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=334">Encyclopedia of Combinatorial Structures 334</a>.
%H A008604 Luis Manuel Rivera, <a href="http://arxiv.org/abs/1406.3081">Integer sequences and k-commuting permutations</a>, arXiv preprint arXiv:1406.3081 [math.CO], 2014-2015.
%H A008604 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F A008604 G.f.: 22*x/(x-1)^2. - _Vincenzo Librandi_, Jun 10 2013
%F A008604 a(n) = A008593(2n). - _Daniel Forgues_, Feb 22 2016
%F A008604 From _Wesley Ivan Hurt_, May 19 2024: (Start)
%F A008604 a(n) = 22*n.
%F A008604 a(n) = 2*a(n-1) - a(n-2). (End)
%F A008604 E.g.f.: 22*x*exp(x). - _Stefano Spezia_, Mar 02 2025
%t A008604 Range[0, 1500, 22] (* _Vladimir Joseph Stephan Orlovsky_, Jun 01 2011 *)
%t A008604 CoefficientList[Series[22 x / (x - 1)^2, {x, 0, 60}], x] (* _Vincenzo Librandi_, Jun 10 2013 *)
%t A008604 LinearRecurrence[{2,-1},{0,22},50] (* _Harvey P. Dale_, Aug 06 2018 *)
%o A008604 (PARI) a(n)=22*n \\ _Charles R Greathouse IV_, Oct 07 2015
%Y A008604 Cf. A008593, A008602, A008603.
%K A008604 nonn,easy
%O A008604 0,2
%A A008604 _N. J. A. Sloane_