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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 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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