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 A022279 #30 Jul 15 2018 13:53:56
%S A022279 0,11,43,96,170,265,381,518,676,855,1055,1276,1518,1781,2065,2370,
%T A022279 2696,3043,3411,3800,4210,4641,5093,5566,6060,6575,7111,7668,8246,
%U A022279 8845,9465,10106,10768,11451,12155
%N A022279 a(n) = n*(21*n + 1)/2.
%H A022279 G. C. Greubel, <a href="/A022279/b022279.txt">Table of n, a(n) for n = 0..5000</a>
%H A022279 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3, -3, 1).
%F A022279 a(n) = 21*n + a(n-1) - 10 for n>0, a(0)=0. - _Vincenzo Librandi_, Aug 04 2010
%F A022279 a(0)=0, a(1)=11, a(2)=43; for n>2, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - _Harvey P. Dale_, May 06 2014
%F A022279 a(n) = A000217(11*n) - A000217(10*n). - _Bruno Berselli_, Oct 13 2016
%F A022279 From _G. C. Greubel_, Aug 23 2017: (Start)
%F A022279 G.f.: x*(10*x + 11)/(1-x)^3.
%F A022279 E.g.f.: (x/2)*(21*x + 22)*exp(x). (End)
%t A022279 Table[n (21 n + 1)/2, {n, 0, 100}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 07 2011 *)
%t A022279 LinearRecurrence[{3, -3, 1}, {0, 11, 43}, 40] (* _Harvey P. Dale_, May 06 2014 *)
%o A022279 (PARI) a(n)=n*(21*n+1)/2 \\ _Charles R Greathouse IV_, Jun 16 2017
%Y A022279 Cf. similar sequences listed in A022289.
%K A022279 nonn,easy
%O A022279 0,2
%A A022279 _N. J. A. Sloane_