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 A054401 #12 Jul 31 2015 11:21:09
%S A054401 0,8,60,368,2100,11528,61740,325088,1690980,8717048,44633820,
%T A054401 227363408,1153594260,5835080168,29443836300,148292923328,
%U A054401 745759583940,3745977788888,18798608421180,94267920012848,472439111692020,2366593604971208
%N A054401 5^n-4^n-1.
%H A054401 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (10, -29, 20).
%F A054401 a(1)=0, a(2)=8, a(3)=60, a(n)=10*a(n-1)-29*a(n-2)+20*a(n-3). - _Harvey P. Dale_, Aug 27 2013
%t A054401 Table[5^n-4^n-1,{n,40}] (* _Vladimir Joseph Stephan Orlovsky_, Feb 15 2011*)
%t A054401 LinearRecurrence[{10,-29,20},{0,8,60},30] (* _Harvey P. Dale_, Aug 27 2013 *)
%Y A054401 Cf. A155626
%K A054401 nonn
%O A054401 1,2
%A A054401 _N. J. A. Sloane_, May 22 2000