OFFSET
1,1
COMMENTS
If instead we allow overlapping occurrences, then the bound is k^n + n - 1 and is achieved for all k, n >= 1 through de Bruijn sequences.
LINKS
D. Gabric and J. Shallit, Avoidance of split overlaps, arxiv preprint arXiv:2002.01968 [cs.DM], February 5 2020.
EXAMPLE
For n = 1..6 the lexicographically least strings of length a(n) are
1: 01
2: 0001110
3: 0000010101111100
4: 01010100100110110111111100000001
5: 00000000010001000110011001110100101010101101101111111110000
6: 0000000000010000100001100011000111001110011110100010100\
1010010110010011011011010101010111011101111111111100000
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jeffrey Shallit, Feb 07 2020
EXTENSIONS
a(6) from Bert Dobbelaere, Feb 08 2020
STATUS
approved