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A352745
a(n) is the number of Lyndon factors of the Fibonacci string of length n.
2
1, 1, 1, 2, 2, 3, 4, 4, 6, 5, 8, 6, 10, 7, 12, 8, 14, 9, 16, 10, 18, 11, 20, 12, 22, 13, 24, 14, 26, 15, 28, 16, 30, 17, 32, 18, 34, 19, 36, 20, 38, 21, 40, 22, 42, 23, 44
OFFSET
0,4
COMMENTS
The Fibonacci string of length n is defined Fibonacci(n) = cat(Fibonacci(n - 1), Fibonacci(n - 2)) for 1 < n and the initial conditions Fibonacci(0) = "1" and Fibonacci(1) = "0", where 'cat' is the operation of concatenating strings. The length of Fibonacci(n) is A352744(1, n). The sequence starts: "1", "0", "01", "010", "01001", "01001010", ...
Apart from the first four terms seems to be identical with A117248.
LINKS
Guy Melançon, Lyndon factorization of infinite words, STACS 96 (Grenoble, 1996), 147-154, Lecture Notes in Comput. Sci., 1046, Springer, Berlin, 1996.
Wikipedia, Lyndon word
EXAMPLE
The Lyndon factorization of the Fibonacci strings of length n = 0..9.
[0] ["1"]
[1] ["0"]
[2] ["01"]
[3] ["01", "0"]
[4] ["01", "001"]
[5] ["01", "00101", "0"]
[6] ["01", "00101", "001", "001"]
[7] ["01", "00101", "0010010100101", "0"]
[8] ["01", "00101", "0010010100101", "00100101", "001", "001"]
[9] ["01", "00101", "0010010100101", "0010010100100101001010010010100101", "0"]
MAPLE
with(StringTools): A352745 := n -> nops(LyndonFactors(Fibonacci(n))):
seq(A352745(n), n = 0..12);
KEYWORD
nonn,more
AUTHOR
Peter Luschny, Apr 06 2022
STATUS
approved