login
A365519
Moebius inversion of A015134.
0
1, 1, 1, 2, 2, 1, 3, 4, 3, 2, 13, 4, 6, 3, 8, 8, 8, 9, 21, 8, 24, 13, 11, 16, 10, 6, 9, 12, 62, 8, 33, 16, 24, 24, 24, 36, 18, 63, 24, 32, 42, 24, 21, 48, 24, 33, 69, 64, 21, 10, 32, 24, 26, 27, 144, 48, 40, 62, 61, 32, 62, 99, 72, 32, 48, 24, 33, 96, 88, 24
OFFSET
1,4
FORMULA
a(n) = Sum_{d|n} moebius(d)*A015134(n/d).
A015134(n) = Sum_{d|n} a(d).
EXAMPLE
For n=4, the a(4) = 2 cycles counted are
{0 1 1 2 3 1} repeating
{0 3 3 2 1 3} repeating
There are 2 other cycles {0} and {0 2 2} mod 4 which are not counted because they are multiples of cycles counted at earlier n (n=1 for {0} and n=2 for {0 1 1}*2 = {0 2 2}).
MATHEMATICA
a[n_]:=Sum[MoebiusMu[d]Part[ResourceFunction["OEISSequence"]["A015134"], n/d], {d, Divisors[n]}]; Array[a, 70] (* Stefano Spezia, Sep 27 2023 *)
CROSSREFS
Sequence in context: A091594 A118032 A089692 * A349346 A066201 A303273
KEYWORD
nonn
AUTHOR
Jay Anderson, Sep 07 2023
STATUS
approved