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 A318122 #6 Aug 22 2018 02:32:25
%S A318122 1,1,1,2,3,4,5,6,8,8,13,10,16,18,21,20,28,20,30,50,36,26,67,58,48,46,
%T A318122 72,64,76,56,93,72,96,96,138,126,112,102,160,114,160,150,144,126,128,
%U A318122 118,273,190,252,130,230,180,260,248,312,212,208,320,422,460,296,452,493,260,436,280
%N A318122 a(0) = a(1) = 1; a(n) = Sum_{k=0..n-2} gcd(a(k), a(n-k-2)).
%H A318122 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%t A318122 a[0] = a[1] = 1; a[n_] := a[n] = Sum[GCD[a[k], a[n - k - 2]], {k, 0, n - 2}]; Table[a[n], {n, 0, 65}]
%Y A318122 Cf. A007464, A007477, A318123.
%K A318122 nonn
%O A318122 0,4
%A A318122 _Ilya Gutkovskiy_, Aug 18 2018