OFFSET
1,2
COMMENTS
This is the lexicographically first such sequence starting with a(1)=1 and being always extended with the smallest integer not yet present that doesn't lead to a contradiction.
LINKS
Jean-Marc Falcoz, Table of n, a(n) for n = 1..1001
EXAMPLE
The blocks of even digits are indicated here by parentheses; the successive block-sizes are 1, 2, 3, 4, 6, 5,... which reproduces the sequence itself:
1,(2),3,(4,6),5,7,(8,20),9,1(0,22,2)1,11,1(2,24,26,2)3,13,1(4,28,40),15...
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Eric Angelini and Jean-Marc Falcoz, Jul 25 2016
STATUS
approved