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A080326 Denominator of Sum(k^mu(k): 1<=k<=n), where mu is the Moebius function (A008683). 5
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

Table of n, a(n) for n=1..30.

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 A084343 A083907

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 November 23 22:48 EST 2014. Contains 249866 sequences.