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 "3" of the sequence [0,1,2,3,30]; then there is 1 digit between the next pair of "3": [30,31]; then there are 2 digits between the next pair of "3": [31,4,32]; then there are 3 digits between the next pair of "3": [32,5,6,34]; then there are 30 digits between the next pair of "3" [34,7,8,9,10,11,12,14,15,16,17,18,19,20,21,22,24,35], etc. The quantities 0, 1, 2, 3, 30,... rebuild the starting sequence.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Eric Angelini and Lars Blomberg, May 23 2016
STATUS
approved