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
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Nov 05 2006
STATUS
approved