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 A026432 #14 Feb 06 2025 13:51:05
%S A026432 1,3,4,5,6,7,8,9,10,12,13,15,16,18,21,22,24,25,28,30,32,33,36,37,40,
%T A026432 42,43,45,46,48,50,52,54,56,57,58,60,61,66,67,68,70,72,73,75,76,78,80,
%U A026432 81,82,84,85,86,88,91,92,93,94,96,97
%N A026432 a(n) = least positive integer > a(n-1) and not a(i)*a(j)-1 for 1<=i<j<=n, with initial terms 1,3.
%H A026432 Ivan Neretin, <a href="/A026432/b026432.txt">Table of n, a(n) for n = 1..1000</a>
%t A026432 a = {1, 3}; used = {a[[1]]*a[[2]] - 1}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; used = Union[used, k*a - 1]; AppendTo[a, k], {n, 3, 60}]; a (* _Ivan Neretin_, Mar 06 2016 *)
%Y A026432 Cf. A026431 and references therein.
%K A026432 nonn
%O A026432 1,2
%A A026432 _Clark Kimberling_
%E A026432 Name clarified by _Robert C. Lyons_, Feb 06 2025