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A267311 Number of factors of length 2n of the Thue-Morse sequence (A010060) that are abelian squares. 0
2, 4, 4, 10, 8, 24, 10, 22, 12, 36, 20, 52, 24, 54, 20, 46, 24, 72, 32, 76, 32, 80, 40, 108, 42, 94, 42, 110, 50, 122, 42, 94, 44, 132, 60, 148, 60, 140, 60, 156, 68, 172, 68, 164, 68, 180, 84, 220, 88, 198, 76, 190, 80, 218, 92, 222, 88, 210, 92, 246, 104, 246, 84, 190, 88, 264, 112, 268, 104, 248 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A "factor" is a contiguous block.  An "abelian square" is a word of the form x x' where x' is a permutation of x.

LINKS

Table of n, a(n) for n=1..70.

Gabriele Fici, Filippo Mignosi, Jeffrey Shallit, Abelian-Square-Rich Words, arXiv:1701.00948 [cs.DM], 2016. See Table 1 p. 6.

EXAMPLE

For n = 3 the three factors of length 6 are 001100, 101101, 010010, 110011.

CROSSREFS

Cf. A010060.

Sequence in context: A126138 A247570 A054764 * A118336 A193852 A327544

Adjacent sequences:  A267308 A267309 A267310 * A267312 A267313 A267314

KEYWORD

nonn

AUTHOR

Jeffrey Shallit, Jan 12 2016

STATUS

approved

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Last modified November 28 04:31 EST 2021. Contains 349400 sequences. (Running on oeis4.)