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A089964
Numbers k such that the denominator of Sum_{j=1..k} mu(j)/j equals Product_{prime p<=k} p.
1
1, 2, 3, 4, 5, 10, 11, 12, 13, 22, 23, 24, 25, 33, 38, 46, 47, 48, 49, 50, 57, 62, 63, 64, 65, 87, 88, 89, 90, 91, 92, 102, 103, 104, 130, 131, 132, 133, 138, 139, 140, 161, 162, 163, 164, 165, 170, 171, 172, 173, 178, 179, 180, 181, 186, 187, 188, 189, 237, 249, 250
OFFSET
1,2
LINKS
FORMULA
Does lim_{n->infinity} a(n)/(n*log(n)) = 1?
MATHEMATICA
seq[nmax_] := Module[{s = {}, sum = 0, n = 1, r = 1}, While[n <= nmax, sum += MoebiusMu[n]/n; If[PrimeQ[n], r *= n]; If[Denominator[sum] == r, AppendTo[s, n]]; n++]; s]; seq[250] (* Amiram Eldar, Jun 17 2022 *)
CROSSREFS
Cf. A008683.
Sequence in context: A375514 A047596 A199502 * A210495 A179302 A240083
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 17 2004
STATUS
approved