A215330 Smooth Lyndon words with 4 colors.

1, 4, 3, 8, 18, 47, 108, 268, 638, 1553, 3761, 9189, 22453, 55185, 135894, 335906, 832312, 2068066, 5149845, 12852750, 32138353, 80509495, 202013368, 507669048, 1277586867, 3219366610, 8122275225

Offset

0,2

Comments

We call a Lyndon word (x[1],x[2],...,x[n]) smooth if abs(x[k]-x[k-1]) <= 1 for 2<=k<=n.

Links

Table of n, a(n) for n=0..26.

Example

(See A215329).

Crossrefs

Cf. A215329 (smooth necklaces, 4 colors), A215328 (smooth Lyndon words, 3 colors).

Sequence in context: A198179 A137503 A320263 * A108624 A108623 A248248

Adjacent sequences: A215327 A215328 A215329 * A215331 A215332 A215333

Keyword

nonn,more

Author

Joerg Arndt, Aug 08 2012

Extensions

More terms from Joerg Arndt, Jun 17 2019

Status

approved