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 A026458 #15 Jul 22 2025 13:22:29
%S A026458 3,4,5,6,7,8,9,11,12,14,15,17,20,21,23,24,27,29,32,35,36,37,39,41,44,
%T A026458 45,47,48,50,51,55,56,57,59,60,62,63,65,69,71,72,74,76,77,80,81,84,87,
%U A026458 89,91,92,93,95,99,101,102,104,105,107,108
%N A026458 a(n) = least positive integer > a(n-1) and not a(i)*a(j)-2 for 1<=i<j<=n.
%C A026458 Apparently the same as A026454 without the leading 1.- _R. J. Mathar_, Jul 22 2025
%H A026458 Ivan Neretin, <a href="/A026458/b026458.txt">Table of n, a(n) for n = 1..1000</a>
%t A026458 a = {3, 4}; used = {a[[1]]*a[[2]] - 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; used = Union[used, k*a - 2]; AppendTo[a, k], {n, 3, 60}]; a (* _Ivan Neretin_, Mar 06 2016 *)
%Y A026458 Cf. A026453 and references therein.
%K A026458 nonn
%O A026458 1,1
%A A026458 _Clark Kimberling_
%E A026458 Definition corrected by _Harvey P. Dale_, Oct 16 2014