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 A107401 #12 Jul 31 2015 17:48:40
%S A107401 0,1,1,2,3,8,10,31,36,117,133,438,495,1636,1846,6107,6888,22793,25705,
%T A107401 85066,95931,317472,358018,1184823,1336140,4421821,4986541,16502462,
%U A107401 18610023,61588028,69453550,229849651,259204176,857810577,967363153
%N A107401 a(n) = -a(n-1)+4*a(n-2)+4*a(n-3)-a(n-4)-a(n-5).
%H A107401 Harvey P. Dale, <a href="/A107401/b107401.txt">Table of n, a(n) for n = 0..1000</a>
%H A107401 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (-1, 4, 4, -1, -1).
%F A107401 G.f.:-x*(3*x^3+x^2-2*x-1)/((x+1)*(x^4-4*x^2+1)). [From Maksym Voznyy (voznyy(AT)mail.ru), Aug 12 2009]
%F A107401 a(2n) = A102871(n+1).
%t A107401 n = 4 M = {{0, 1, 0, 0, 0}, {0, 0, 1, 0, 0}, {0, 0, 0, 1, 0}, {0, 0, 0, 0, 1}, {-1, -1, m, m, -1}} Expand[Det[M - x*IdentityMatrix[5]]] NSolve[Det[M - x*IdentityMatrix[5]] == 0, x] v[1] = {0, 1, 1, 2, 3} digits = 50 v[n_] := v[n] = M.v[n - 1] a = Table[v[n][[1]], {n, 1, digits}]
%t A107401 LinearRecurrence[{-1,4,4,-1,-1},{0,1,1,2,3},40] (* _Harvey P. Dale_, Aug 16 2011 *)
%K A107401 nonn,easy
%O A107401 0,4
%A A107401 _Roger L. Bagula_, May 25 2005
%E A107401 Definition replaced by recurrence by the Associate Editors of the OEIS, Sep 28 2009