cp's OEIS Frontend

A316765 A self-"read and extend" sequence built following the three rules given in the Comments section.

%I A316765 #12 Aug 26 2018 01:08:44
%S A316765 1,0,2,6,18,9,27,13,39,19,9,4,2,1,0,0,0,0,0,0,3,5,7,8,10,11,5,2,1,3,1,
%T A316765 12,6,3,1,3,1,0,0,0,0,0,0,0,0,0,14,15,16,17,20,21,22,23,24,12,36,18,9,
%U A316765 4,12,6,3,9,25,75,37,111,333,999,499,1497,4491,2245,6735,3367,10101,5050,15150,7575
%N A316765 A self-"read and extend" sequence built following the three rules given in the Comments section.
%C A316765 Start with a(1) = 1 and read the sequence digit by digit starting from the left:
%C A316765 when the read digit is odd, we divide by 2 the last term of the sequence, then extend the sequence with the entire part of the result;
%C A316765 when the read digit is even (but not 0), we multiply by 3 the last term of the sequence, then extend the sequence with the result;
%C A316765 when the read digit is 0, we extend the sequence with the smallest integer not yet present in the sequence.
%H A316765 Jean-Marc Falcoz, <a href="/A316765/b316765.txt">Table of n, a(n) for n = 1..10001</a>
%e A316765 The odd digit 1 divides 1 by two (which is 0,5), and |0,5| is 0;
%e A316765 the digit 0 extends the sequence with the smallest integer not present yet in the sequence, which is 2;
%e A316765 the digit 2 multiplies 2 by three, which is 6;
%e A316765 the digit 6 multiplies 6 by three, which is 18;
%e A316765 the odd digit 1 divides 18 by two, which is 9;
%e A316765 the digit 8 multiplies 9 by three, which is 27; etc.
%Y A316765 Cf. (for more self-"read and extend" sequences) A316749, A316750, A316758, A316764.
%K A316765 base,nonn,look
%O A316765 1,3
%A A316765 _Eric Angelini_ and _Jean-Marc Falcoz_, Jul 12 2018