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 A077827 #12 May 21 2018 15:12:22
%S A077827 1,3,9,27,79,231,675,1971,5755,16803,49059,143235,418195,1220979,
%T A077827 3564819,10407987,30387571,88720755,259032627,756281907,2208070579,
%U A077827 6446770227,18822245427,54954172467,160446376243,468445588275,1367692273971,3993168476979,11658612678451
%N A077827 Expansion of (1-x)^(-1)/(1-2*x-2*x^2-2*x^3).
%H A077827 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (3,0,0,-2).
%t A077827 CoefficientList[Series[(1-x)^(-1)/(1-2x-2x^2-2x^3),{x,0,40}],x] (* _Harvey P. Dale_, Mar 27 2011 *)
%o A077827 (PARI) Vec((1-x)^(-1)/(1-2*x-2*x^2-2*x^3)+O(x^99)) \\ _Charles R Greathouse IV_, Sep 27 2012
%Y A077827 Partial sums of S(n, x), for x=1...11, A021823, A000217, A027941, A061278, A089817, A053142, A092521, A076765, A092420, A097784, A097826.
%K A077827 nonn,easy
%O A077827 0,2
%A A077827 _N. J. A. Sloane_, Nov 17 2002, Jun 05 2007