A029809 Number of Lyndon words (aperiodic necklaces) with 4n beads of 4 colors, n beads of each color. One color labeled, the other 3 unlabeled.

1, 52, 5133, 656880, 97772875, 16032938340, 2812609211657, 518547356184000, 99318297529004400, 19605670296090989500, 3966181169996511862429, 818782296743542722132528, 171938262068874336023196923

Offset

1,2

Links

Table of n, a(n) for n=1..13.

Index entries for sequences related to Lyndon words

Formula

1/(24n) * sum over d|n of {mu(n/d) * (4d)! / d!^4}.

Prog

(PARI) for(n=1, 23, print(1/(24*n)*sumdiv(n, d, moebius(n/d)*(4*d)!/d!^4)))

Crossrefs

Inverse Witt transform of A006179.

Sequence in context: A360444 A027550 A006179 * A200576 A295450 A306283

Adjacent sequences: A029806 A029807 A029808 * A029810 A029811 A029812

Keyword

nonn

Author

Lionel Levine (levine(AT)ultranet.com)

Extensions

More terms from Jason Earls, Aug 31 2001

Edited by Christian G. Bower, Aug 29 2002

Status

approved