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 A120771 #13 Feb 19 2016 18:24:09
%S A120771 1,0,0,1,1,1,3,2,1,6,5,3,14,11,6,31,25,14,70,56,31,157,126,70,353,283,
%T A120771 157,793,636,353,1782,1429,793,4004,3211,1782,8997,7215,4004,20216,
%U A120771 16212,8997,45425,36428,20216,102069,81853,45425,229347,183922,102069,515338,413269,229347,1157954,928607,515338
%N A120771 Expansion of ( 1-x^3+x^4+x^5-x^8 ) / ( 1-2*x^3-x^6+x^9 ).
%H A120771 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,2,0,0,1,0,0,-1).
%F A120771 Three consecutive coefficients are generated from the left row of the n-th power of the matrix [1,1,1; 1,1,0; 1,0,0].
%t A120771 CoefficientList[Series[(1-x^3+x^4+x^5-x^8)/(1-2*x^3-x^6+x^9),{x,0,60}],x] (* or *) LinearRecurrence[{0,0,2,0,0,1,0,0,-1},{1,0,0,1,1,1,3,2,1},60] (* _Harvey P. Dale_, Feb 19 2016 *)
%Y A120771 Cf. A077998 (trisection), A006054 (trisection), A006356 (trisection), A038196.
%K A120771 nonn,easy
%O A120771 0,7
%A A120771 _Gary W. Adamson_, Jul 03 2006