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 A080306 Numerator of Sum(k^mu(k): 1<=k<=n), where mu is the Moebius function (A008683). 5
 1, 3, 11, 17, 91, 271, 1927, 2137, 2347, 4447, 49127, 51437, 670991, 1091411, 1541861, 1571891, 26752177, 27262687, 518501563, 528201253, 731894743, 945287923, 21751321919, 21974414789, 22197507659, 27997922279, 28221015149 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE a(6) = 1^mu(1)+2^mu(2)+3^mu(3)+4^mu(4)+5^mu(5)+6^mu(6) = 1^1+2^(-1)+3^(-1)+4^0+5^(-1)+6^1 = 1 + 1/2 + 1/3 + 1 + 1/5 + 6 = (30+15+10+30+6+180)/30 = 271/30, therefore a(6)=271, A080326(6)=30. PROG (PARI) a(n) = numerator(sum(k = 1, n, k^moebius(k))); \\ Michel Marcus, Aug 29 2013 CROSSREFS Denominators are in A080326. Cf. A080304, A080305. Sequence in context: A145701 A072982 A124787 * A036448 A128346 A128031 Adjacent sequences:  A080303 A080304 A080305 * A080307 A080308 A080309 KEYWORD nonn,frac AUTHOR Reinhard Zumkeller, Feb 13 2003 STATUS approved

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Last modified July 17 02:10 EDT 2019. Contains 325092 sequences. (Running on oeis4.)