OFFSET
1,3
COMMENTS
This is the lexicographically first such sequence, starting with a(1)=0 that has always been extended with the smallest integer not already present in the sequence and not leading to a contradiction.
EXAMPLE
There are 0 digits between the first two "1" of the sequence [0,1,10,]; then there is 1 digit between the next pair of "1" [10,12,]; then there are 10 digits between the next pair of "1" [12,2,3,4,5,6,7,8,9,21]; then there are 12 digits between the next pair of "1" [21,20,22,23,24,25,26,13]; then there are 2 digits between the next pair of "1" [13,31], etc. The quantities 0, 1, 10, 12, 2,... rebuild the starting sequence.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Eric Angelini, May 23 2016
STATUS
approved