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A352746
a(n) is the number of Lyndon factors of the Thue-Morse string of length n.
2
0, 1, 1, 1, 2, 2, 3, 4, 3, 3, 4, 5, 4, 5, 4, 4, 5, 4, 5, 6, 5, 6, 5, 5, 6, 7, 6, 5, 6, 5, 6, 7, 6, 5, 6, 7, 6, 7, 6, 6, 7, 8, 7, 6, 7, 6, 7, 8, 7, 8, 7, 7, 8, 6, 7, 8, 7, 6, 7, 8, 7, 8, 7, 7, 8, 6, 7, 8, 7, 8, 7, 7, 8, 9, 8, 7, 8, 7, 8, 9, 8, 9, 8, 8, 9, 7, 8
OFFSET
0,5
COMMENTS
The Thue-Morse string of length n is the length-n prefix of the infinite Thue-Morse string. The sequence starts: "", "0", "01", "011", "0110", "01101", "011010", ...
LINKS
Augustin Ido and Guy Melançon, Lyndon factorization of the Thue-Morse word and its relatives, Discret. Math. Theor. Comput. Sci. 1997.
Wikipedia, Lyndon word
EXAMPLE
The Lyndon factorization of the Thue-Morse strings of length n = 0..9.
[0] []
[1] ["0"]
[2] ["01"]
[3] ["011"]
[4] ["011", "0"]
[5] ["011", "01"]
[6] ["011", "01", "0"]
[7] ["011", "01", "0", "0"]
[8] ["011", "01", "001"]
[9] ["011", "01", "0011"]
MAPLE
with(StringTools): A352746 := n -> nops(LyndonFactors(ThueMorse(n))):
seq(A352746(n), n = 0..12);
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Apr 06 2022
STATUS
approved