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 A016267 #21 Sep 04 2017 03:52:03
%S A016267 1,23,387,5755,80171,1073163,13989067,178979915,2258870091,
%T A016267 28217552203,349721737547,4307771961675,52804374651211,
%U A016267 644763606925643,7848274394218827,95290403841737035,1154595957211955531
%N A016267 Expansion of 1/((1-x)(1-10x)(1-12x)).
%H A016267 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (23,-142,120).
%F A016267 a(n) = (54*12^(n+1) - 55*10^(n+1) + 1)/99. - _Bruno Berselli_, Mar 21 2011
%F A016267 a(n) = 22*a(n-1) - 120*a(n-2) + 1, n >= 2. - _Vincenzo Librandi_, Mar 21 2011
%F A016267 a(0)=1, a(1)=23, a(2)=387, a(n) = 23*a(n-1) - 142*a(n-2) + 120*a(n-3). - _Harvey P. Dale_, May 03 2012
%t A016267 CoefficientList[Series[1/((1-x)(1-10x)(1-12x)),{x,0,30}],x] (* or *) LinearRecurrence[{23,-142,120},{1,23,387},30] (* _Harvey P. Dale_, May 03 2012 *)
%K A016267 nonn
%O A016267 0,2
%A A016267 _N. J. A. Sloane_