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 A077897 #9 Nov 02 2024 15:18:50
%S A077897 1,0,3,-1,8,-6,22,-25,64,-91,195,-312,612,-1040,1953,-3420,6287,
%T A077897 -11173,20328,-36386,65870,-118313,213668,-384423,693447,-1248624,
%U A077897 2251096,-4054896,7308465,-13167160,23729195,-42755049,77046280,-138827182,250164694,-450772777,812274984,-1463655843
%N A077897 Expansion of (1-x)^(-1)/(1+x-2*x^2-x^3).
%H A077897 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,3,-1,-1)
%t A077897 CoefficientList[Series[(1-x)^(-1)/(1+x-2x^2-x^3),{x,0,40}],x] (* or *) LinearRecurrence[{0,3,-1,-1},{1,0,3,-1},40] (* _Harvey P. Dale_, Nov 02 2024 *)
%o A077897 (PARI) Vec((1-x)^(-1)/(1+x-2*x^2-x^3)+O(x^99)) \\ _Charles R Greathouse IV_, Sep 27 2012
%K A077897 sign,easy
%O A077897 0,3
%A A077897 _N. J. A. Sloane_, Nov 17 2002