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 A133293 #26 Dec 12 2023 08:51:57
%S A133293 0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,
%T A133293 1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,
%U A133293 2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5,-3,-2,-1,0,1,2,3,-5,5
%N A133293 First differences of A133292.
%C A133293 Periodic with period 9. - _Colin Barker_, Apr 04 2015
%H A133293 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (-1, -1, -1, -1, -1, -1, -1, -1).
%F A133293 G.f.: x*(x^6+3*x^5+6*x^4+x^3+6*x^2+3*x+1) / ((x^2+x+1)*(x^6+x^3+1)). - _Colin Barker_, Apr 04 2015
%t A133293 Differences[PadRight[{},111,{1,1,2,4,7,2,7,4,2}]] (* _Harvey P. Dale_, Apr 29 2012 *)
%t A133293 LinearRecurrence[{-1, -1, -1, -1, -1, -1, -1, -1},{0, 1, 2, 3, -5, 5, -3, -2},105] (* _Ray Chandler_, Aug 26 2015 *)
%o A133293 (PARI) concat(0, Vec(x*(x^6+3*x^5+6*x^4+x^3+6*x^2+3*x+1)/((x^2+x+1)*(x^6+x^3+1)) + O(x^100))) \\ _Colin Barker_, Apr 04 2015
%K A133293 sign,easy
%O A133293 0,3
%A A133293 _Paul Curtz_, Oct 17 2007