%I #11 Dec 26 2017 17:31:30
%S 1,3,5,2,7,8,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,
%T 47,49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,83,85,87,89,91,
%U 93,95,97,99,110,10,12,14,16,111,28,30,32,34,36,48,50,52
%N Self-describing sequence: sequence starts with a(1) = 1 and a(n) is chosen to be the smallest positive number not already in the sequence such that the assertion "sequence gives the positions of the odd digits when the sequence is read as a string of digits" is true.
%C Inspired by Angelini's sequence A114308.
%H Jean-Marc Falcoz, <a href="/A125132/b125132.txt">Table of n, a(n) for n = 1..2001</a>
%e Here are the digits strung together (the odd digits occur at positions that are indexed by terms of the sequence):
%e -135278911
%e 1315171921
%e 2325272931
%e 3335373941...
%e Explanation: a(2)=2? No. a(2)=3? Yes, but then the third term has to be odd and 2 has to appear later. a(3)=2? No, a(3) must be odd, so 5. a(4)? Now we can fill in the 2 that has been waiting. And so on.
%Y Cf. A125133 (missing numbers), A114308 (same except need a(n) > a(n-1)).
%K base,easy,nonn
%O 1,2
%A _N. J. A. Sloane_, Jan 12 2007
%E Corrected and extended by _D. S. McNeil_, Oct 22 2011