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 A225500 #12 Nov 17 2016 09:43:23
%S A225500 1,1,1,1,1,2,2,3,4,5,7,9,12,15,19,25,33,43,56,73,95,124,161,210,273,
%T A225500 355,463,603,786,1023,1332,1735,2259,2942,3831,4989,6497,8461,11019,
%U A225500 14350,18687,24335,31691,41270,53745
%N A225500 Expansion of 1/(1 - x - x^5 + x^6 - x^7 - x^11 + x^12).
%H A225500 G. C. Greubel, <a href="/A225500/b225500.txt">Table of n, a(n) for n = 0..1000</a>
%H A225500 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,1,-1,1,0,0,0,1,-1).
%t A225500 CoefficientList[Series[1/(1 - x - x^5 + x^6 - x^7 - x^11 + x^12), {x, 0, 50}], x]
%t A225500 LinearRecurrence[{1,0,0,0,1,-1,1,0,0,0,1,-1},{1,1,1,1,1,2,2,3,4,5,7,9},100] (* _G. C. Greubel_, Nov 16 2016 *)
%o A225500 (PARI) Vec(1/(1-x -x^5 +x^6 -x^7 -x^11 +x^12) + O(x^50)) \\ _G. C. Greubel_, Nov 16 2016
%Y A225500 Cf. A117791, A107293, A204631, A225391, A225482, A225484, A225490, A225490.
%K A225500 nonn,easy
%O A225500 0,6
%A A225500 _Roger L. Bagula_, May 09 2013