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A229617
Number of binary strings of length n containing at most 3 distinct squares, where a square is a nonempty block of the form xx.
0
1, 2, 4, 8, 16, 32, 64, 128, 210, 324, 438, 588, 758, 928, 1100, 1300, 1400, 1506, 1580, 1624, 1574, 1536, 1550, 1584, 1600, 1644, 1718, 1800, 1910, 2076, 2272, 2484, 2736, 3004, 3306, 3612, 4044, 4456, 4800, 5188, 5664, 6164, 6760, 7380, 7980
OFFSET
0,2
LINKS
R. C. Entringer, D. E. Jackson and J. A. Schatz, On nonrepetitive sequences, J. Combin. Theory Ser. A. 16 (1974), 159-164.
CROSSREFS
Sequence in context: A009641 A089889 A297526 * A306316 A275061 A230177
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, Sep 26 2013
STATUS
approved