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 A089086 #9 Feb 12 2019 04:48:25
%S A089086 5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,
%T A089086 2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,
%U A089086 10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5,2,1,2,1,10,1,2,1,2,5
%N A089086 Greatest common divisor of n^2-5 and n^2+5.
%H A089086 Harvey P. Dale, <a href="/A089086/b089086.txt">Table of n, a(n) for n = 0..1000</a>
%t A089086 GCD@@#&/@Table[n^2+{5,-5},{n,0,110}] (* _Harvey P. Dale_, Jul 17 2016 *)
%o A089086 (PARI) g(n) = for(x=0,n,print1(gcd(x^2-5,x^2+5)","))
%Y A089086 Cf. A109013.
%K A089086 easy,nonn
%O A089086 0,1
%A A089086 _Cino Hilliard_, Dec 05 2003