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 A225394 #21 Sep 08 2022 08:46:05
%S A225394 1,1,2,3,5,8,13,20,32,51,81,129,205,326,519,826,1314,2091,3327,5294,
%T A225394 8424,13404,21328,33937,54000,85924,136721,217548,346159,550803,
%U A225394 876429,1394560,2219002,3530841,5618219,8939622,14224586,22633938,36014767,57306132,91184618
%N A225394 Expansion of 1/(1 - x - x^2 + x^7 - x^9).
%C A225394 Limiting ratio is 1.59118..., the largest real root of -1 + x^2 - x^7 - x^8 + x^9 = 0.
%H A225394 G. C. Greubel, <a href="/A225394/b225394.txt">Table of n, a(n) for n = 0..1000</a>
%H A225394 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,0,0,0,-1,0,1).
%F A225394 a(n) = a(n-1) + a(n-2) - a(n-7) + a(n-9). - _Ilya Gutkovskiy_, Nov 16 2016
%t A225394 CoefficientList[Series[1/(1 - x - x^2 + x^7 - x^9), {x, 0, 50}], x]
%t A225394 LinearRecurrence[{1,1,0,0,0,0,-1,0,1}, {1,1,2,3,5,8,13,20,32}, 50] (* _G. C. Greubel_, Nov 16 2016 *)
%o A225394 (PARI) Vec(1/(1-x-x^2+x^7-x^9) + O(x^50)) \\ _G. C. Greubel_, Nov 16 2016
%o A225394 (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x-x^2+x^7-x^9))); // _G. C. Greubel_, Nov 03 2018
%Y A225394 Cf. A029826, A117791, A143419, A143438, A143472, A143619, A143644, A147663, A173908, A173911, A173924, A173925, A174522, A175740, A175772, A175773, A175782, A181600, A204631, A225391, A225393, A225482, A225499.
%K A225394 nonn,easy
%O A225394 0,3
%A A225394 _Roger L. Bagula_, May 06 2013