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A124579
Number of natural numbers less than n which have identical Moebius mu values.
1
0, 0, 1, 0, 2, 1, 3, 1, 2, 2, 4, 3, 5, 3, 4, 4, 6, 5, 7, 6, 5, 6, 8, 7, 8, 7, 9, 10, 9, 10, 11, 11, 8, 9, 10, 12, 12, 11, 12, 13, 13, 14, 15, 14, 15, 13, 16, 16, 17, 18, 14, 19, 17, 20, 15, 21, 16, 17, 18, 22, 19, 18, 23, 24, 19, 20, 21, 25, 20, 22, 23, 26, 24, 21, 27, 28, 22, 25, 26, 29
OFFSET
1,5
EXAMPLE
a(10) = 2 because in the first nine integers less than 10, mu(1) = mu(6) = mu(10).
MATHEMATICA
a[n_] := a[n] = MoebiusMu@n; f[n_] := Count[a /@ Range[n - 1], a@n]; Array[f, 80]
With[{mu=MoebiusMu[Range[80]]}, Table[Count[Take[mu, n], _?(#==MoebiusMu[ n+1]&)], {n, 0, Length[mu]}]] (* Harvey P. Dale, Aug 18 2016 *)
CROSSREFS
Cf. A124580.
Sequence in context: A102862 A029331 A037269 * A035306 A101691 A349445
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Nov 05 2006
STATUS
approved