cp's OEIS Frontend

A333811 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).

%I A333811 #10 Apr 10 2020 23:49:03
%S A333811 0,1,2,5,3,7,4,6,8,9,11,15,12,14,13,10,16,17,21,20,25,18,23,19,22,24,
%T A333811 26,29,30,28,31,27,32,33,35,34,36,37,38,39,40,41,42,43,44,45,47,46,48,
%U A333811 50,49,51,52,53,55,54,56,57,59,58,61,60,62,63,64,65,66,67,68,69,70
%N A333811 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).
%C A333811 a(3) = 5 as a(2) ^ a(3) = 2 ^ 5 = 32 which contains '2' as a substring.
%C A333811 a(4) = 3 as a(3) ^ a(4) = 5 ^ 3 = 125 which contains '5' as a substring.
%C A333811 a(5) = 7 as a(4) ^ a(5) = 3 ^ 7 = 2187 which contains '7' as a substring.
%H A333811 Rémy Sigrist, <a href="/A333811/a333811.gp.txt">PARI program for A333811</a>
%o A333811 (PARI) See Links section.
%Y A333811 Cf. A333774, A333775, A332795, A332703.
%K A333811 nonn,base
%O A333811 0,3
%A A333811 _Scott R. Shannon_, Apr 05 2020