A053560 - OEIS

A053560

Number of ternary Lyndon words of length n with trace 0 and subtrace 1 over GF(3).

0, 0, 0, 1, 6, 14, 36, 93, 252, 661, 1782, 4893, 13608, 37890, 106142, 298755, 844182, 2391732, 6797196, 19371684, 55348596, 158491993, 454795398, 1307534319, 3765720066, 10862647236, 31381000560, 90780846494, 262951692390

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OFFSET

1,5

LINKS

Table of n, a(n) for n=1..29.

F. Ruskey, Ternary Lyndon words with given trace and subtrace over GF(3)

FORMULA

(1/n) Sum mu(d) M(n/d, 2, 2); d|n, d=1(3) + (1/n) Sum mu(d) M(n/d, 1, 1); d|n, d=2(3), where M(n, t, s) = Sum n!/(i!j!k!); i+j+k=n, j=t(3), k=s(3)

EXAMPLE

a(4) = 1 = |{ 1122 }|

CROSSREFS

Cf. A053548, A053561, A053562, A053563, A053564.

Sequence in context: A268275 A272548 A036387 * A229441 A119874 A344380

Adjacent sequences: A053557 A053558 A053559 * A053561 A053562 A053563

KEYWORD

nonn

AUTHOR

Frank Ruskey, Jan 17 2000

STATUS

approved