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A080326 Denominator of Sum(k^mu(k): 1<=k<=n), where mu is the Moebius function (A008683). 6
1, 2, 6, 6, 30, 30, 210, 210, 210, 210, 2310, 2310, 30030, 30030, 30030, 30030, 510510, 510510, 9699690, 9699690, 9699690, 9699690, 223092870, 223092870, 223092870, 223092870, 223092870, 223092870, 6469693230, 3234846615 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is a divisor of A034386(n), the product of the primes <= n. Does a(n) = A034386(n) for infinitely many n?

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Accumulate[Table[n^MoebiusMu[n], {n, 30}]]//Denominator (* Harvey P. Dale, Jul 28 2021 *)

PROG

(PARI) a(n) = denominator(sum(k = 1, n, k^moebius(k))); \\ Michel Marcus, Aug 29 2013

CROSSREFS

Numerators are in A080306. Cf. A080304, A080305, A034386.

Sequence in context: A099566 A147299 A090549 * A034386 A083907 A084343

Adjacent sequences:  A080323 A080324 A080325 * A080327 A080328 A080329

KEYWORD

nonn,frac

AUTHOR

Dean Hickerson, Feb 15 2003

STATUS

approved

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Last modified January 24 19:03 EST 2022. Contains 350565 sequences. (Running on oeis4.)