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 A200526 #25 Aug 02 2019 04:10:41
%S A200526 2156316023,211148507797805,392841376460687116573,
%T A200526 13886731309220741899538675431,1359801885649216204023955447726829,
%U A200526 2529908688645864568558938918274367865293,89430911052730984787593270943984417274689212615
%N A200526 a(n) = gcd(t(n), t(3n-1)), where t = A200217.
%C A200526 Successive maxima of the GCD in A200217 occur between A200217(n) and A200217(3n-1) terms. Conjecture: All terms have same set of prime divisors, that can be used to complete prime factorization of every term in this sequence by the GCD method. All prime divisors with exception 19 are of the form 4k+1. The integer 19 divides a(3n+1) for n=0,1,2,3,...
%t A200526 ff = {}; Do[AppendTo[ff, GCD[15/8 Fibonacci[15 (-1 + 2 n)] - 9/20 Fibonacci[30 (-1 + 2 n)] + 1/40 Fibonacci[45 (-1 + 2 n)], 15/8 Fibonacci[15 (-1 + 2 (3 n - 1))] - 9/20 Fibonacci[30 (-1 + 2 (3 n - 1))] + 1/40 Fibonacci[45 (-1 + 2 (3 n - 1))]]], {n, 2, 10}]; ff
%Y A200526 Cf. A200217.
%K A200526 nonn
%O A200526 2,1
%A A200526 _Artur Jasinski_, Nov 18 2011