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A060173 Number of orbits of length n under a map whose periodic points are counted by A056045. 6
1, 1, 1, 2, 1, 6, 1, 12, 10, 30, 1, 139, 1, 252, 231, 920, 1, 3780, 1, 10250, 5601, 32076, 1, 149390, 2126, 400036, 173692, 1475642, 1, 6196651, 1, 19113136, 5864915, 68635494, 201405, 289525026, 1, 930138540, 208267554, 3469290971, 1, 14075005210, 1, 47994721225, 7683440470 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
COMMENTS
The sequence A056045 records the number of points of period n under a map. The number of orbits of length n for this map gives the sequence above.
LINKS
Y. Puri and T. Ward, Arithmetic and growth of periodic orbits, J. Integer Seqs., Vol. 4 (2001), #01.2.1.
Yash Puri and Thomas Ward, A dynamical property unique to the Lucas sequence, Fibonacci Quarterly, Volume 39, Number 5 (November 2001), pp. 398-402.
FORMULA
a(n) = (1/n)* Sum_{ d divides n } mu(d)*A056045(n/d).
EXAMPLE
a(7) = 1 since the map whose periodic points are counted by A056045 has 1 fixed point and 8 points of period 7, hence 1 orbits of length 7.
PROG
(PARI) a056045(n) = sumdiv(n, d, binomial(n, d));
a(n) = (1/n)*sumdiv(n, d, moebius(d)*a056045(n/d)); \\ Michel Marcus, Sep 11 2017
CROSSREFS
Sequence in context: A053785 A233809 A207536 * A059344 A109193 A322672
KEYWORD
easy,nonn
AUTHOR
Thomas Ward, Mar 13 2001
EXTENSIONS
More terms from Michel Marcus, Sep 11 2017
STATUS
approved

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Last modified May 25 12:29 EDT 2024. Contains 372788 sequences. (Running on oeis4.)