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 A207076 #17 Feb 16 2025 08:33:16
%S A207076 0,185,836,1461,2436,6125,9740,15405,36888,57953,90968,216177,338952,
%T A207076 531377,1261148,1976733,3098268,7351685,11522420,18059205,42849936,
%U A207076 67158761,105257936,249748905,391431120,613489385,1455644468,2281428933,3575679348,8484118877
%N A207076 Nonnegative values x of solutions (x, y) to the Diophantine equation x^2 + (x+487)^2 = y^2.
%H A207076 Vincenzo Librandi, <a href="/A207076/b207076.txt">Table of n, a(n) for n = 1..1000</a>
%H A207076 Wikipedia, <a href="http://en.wikipedia.org/wiki/Diophantine_equation">Diophantine equation</a>
%H A207076 MathWorld, <a href="https://mathworld.wolfram.com/DiophantineEquation.html">Diophantine equation</a>
%H A207076 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,6,-6,0,-1,1).
%F A207076 G.f.: x^2*(135*x^5+217*x^4+135*x^3-625*x^2-651*x-185)/((x-1)*(x^6-6*x^3+1)). [_Colin Barker_, Aug 05 2012]
%t A207076 LinearRecurrence[ {1, 0, 6, -6, 0, -1, 1}, {0, 185, 836, 1461, 2436, 6125, 9740}, 50]
%Y A207076 Cf. A207058, A207059, A207060, A207061, A207075
%K A207076 nonn,easy
%O A207076 1,2
%A A207076 _Vladimir Joseph Stephan Orlovsky_, Feb 14 2012