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A320087 Number of primitive (=aperiodic) ternary words with length less than or equal to n which are earlier in lexicographic order than any other word derived by cyclic shifts of the alphabet. 3
1, 3, 11, 35, 115, 347, 1075, 3235, 9787, 29387, 88435, 265315, 796755, 2390347, 7173227, 21519947, 64566667, 193700035, 581120523, 1743362283, 5230145947, 15690440099, 47071499707, 141214499227, 423644035627, 1270932113627, 3812797935395, 11438393826035 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..2096

FORMULA

a(n) = Sum_{j=1..n} Sum_{d|j} 3^(d-1) * mu(j/d).

a(n) = A143327(n,3).

a(n) = Sum_{j=1..n} A143325(j,3).

a(n) = A143326(n,3) / 3.

MAPLE

b:= n-> add(`if`(d=n, 3^(n-1), -b(d)), d=numtheory[divisors](n)):

a:= proc(n) option remember; b(n)+`if`(n<2, 0, a(n-1)) end:

seq(a(n), n=1..30);

CROSSREFS

Column k=3 of A143327.

Partial sums of A034741.

Cf. A008683, A143325, A143326.

Sequence in context: A125672 A107683 A259400 * A014335 A147474 A247417

Adjacent sequences:  A320084 A320085 A320086 * A320088 A320089 A320090

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 05 2018

STATUS

approved

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Last modified March 19 03:59 EDT 2019. Contains 321311 sequences. (Running on oeis4.)