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 A333775 #15 Apr 19 2020 07:51:24 %S A333775 0,1,2,6,4,10,3,5,7,11,8,16,20,21,9,22,51,12,26,24,52,76,28,46,40,31, %T A333775 30,41,15,50,13,25,17,69,34,42,94,100,14,82,71,60,36,38,89,55,61,35, %U A333775 80,56,87,33,75,29,53,101,18,66,151,32,91,43,102,19,63,137,83,96,126,44,59,27,103 %N A333775 a(0) = 0; for n > 0, a(n) is the smallest positive integer not yet appearing in the sequence such that a(n-1) * a(n) contains as a substring either a(n-1) or a(n). %H A333775 Rémy Sigrist, <a href="/A333775/b333775.txt">Table of n, a(n) for n = 0..10000</a> %H A333775 Rémy Sigrist, <a href="/A333775/a333775.gp.txt">PARI program for A333775</a> %e A333775 a(1) = 1 as a(0) * a(1) = 0 * 1 = 0 which contains '0' as a substring. %e A333775 a(4) = 4 as a(3) * a(4) = 6 * 4 = 24 which contains '4' as a substring. %e A333775 a(18) = 26 as a(17) * a(18) = 12 * 26 = 312 which contains '12' as a substring. %o A333775 (PARI) See Links section. %Y A333775 Cf. A333774, A333811, A332795, A332703. %K A333775 nonn,base %O A333775 0,3 %A A333775 _Scott R. Shannon_, Apr 05 2020