A220587 Number of Lyndon words appearing as n-th degree terms in Baker-Campbell-Hausdorff series.

2, 1, 2, 1, 6, 5, 18, 17, 55, 55, 186, 185, 630, 629, 2181, 2181, 7710, 7709, 27594, 27593, 99857, 99857

Offset

1,1

Links

Table of n, a(n) for n=1..22.

Dror Bar-Natan, The BCH series in terms of Lyndon words, MathOverflow.

Dror Bar-Natan, A BCH-Lyndon Question.

Wikipedia, Baker-Campbell-Hausdorff formula

Wikipedia, Lyndon word

Crossrefs

Cf. A001037.

Sequence in context: A276157 A169593 A057568 * A195962 A046749 A016543

Adjacent sequences: A220584 A220585 A220586 * A220588 A220589 A220590

Keyword

nonn,more

Author

Dror Bar-Natan, communicated by Max Alekseyev, Dec 16 2012

Status

approved