OFFSET
1,2
COMMENTS
The sequence starts with a(1) = 1 and was always extended with the smallest available integer not yet present in the sequence. This is the lexicographically first sequence with this property.
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..10000
EXAMPLE
1 + 3 (the next digit) = 4 (even);
3 + 4,2,5 (the next 3 digits) = 14 (even);
4 + 2,5,7,8 (the next 4 digits) = 26 (even);
2 + 5,7 (the next 2 digits) = 14 (even);
...
9 + 1,1,1,3,3,0,2,1,1 = 22 (even);
...
0 + (no digit) = 0 (even).
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Lars Blomberg, Jan 10 2018
STATUS
approved