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 A026464 #11 Oct 30 2018 08:52:04
%S A026464 3,4,5,6,8,9,11,12,15,17,19,20,21,24,26,27,29,32,33,35,36,37,39,40,41,
%T A026464 44,45,47,48,50,51,54,56,57,59,60,63,65,67,68,69,71,72,75,77,80,81,84,
%U A026464 87,89,90,91,92,95,96,99,101,104,105,107
%N A026464 a(n) = least positive integer > a(n-1) and not a(i)*a(j)-2 for 1<=i<=j<=n.
%C A026464 Essentially the same as A026460. [From _R. J. Mathar_, Oct 23 2008]
%H A026464 Christopher R. H. Hanusa, T Zaslavsky, S Chaiken, <a href="http://arxiv.org/abs/1609.00853">A q-Queens Problem. IV. Queens, Bishops, Nightriders (and Rooks)</a>, arXiv preprint arXiv:1609.00853, a12016
%t A026464 a[1] = 3; a[2] = 4; a[n_] := a[n] =
%t A026464 For[k = a[n-1]+1, True, k++, a[n] = k; If[AllTrue[Tuples[Range[n], {2}], k != a[#[[1]]] a[#[[2]]] - 2&], Return[k]]
%t A026464 ];
%t A026464 Array[a, 60] (* _Jean-François Alcover_, Oct 30 2018 *)
%K A026464 nonn
%O A026464 1,1
%A A026464 _Clark Kimberling_