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 A140697 Mobius transform of A000082. 1
 1, 5, 11, 18, 29, 55, 55, 72, 96, 145, 131, 198, 181, 275, 319, 288, 305, 480, 379, 522, 605, 655, 551, 792, 720, 905, 864, 990, 869, 1595, 991, 1152, 1441, 1525, 1595, 1728, 1405, 1895, 1991, 2088, 1721, 3025, 1891, 2358, 2784, 2755, 2255, 3168, 2688, 3600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Dirichlet convolution of the sequence of (absolute values of A055615) and A007434. - R. J. Mathar, Feb 27 2011 LINKS Alois P. Heinz, Table of n, a(n) for n = 1..10000 FORMULA Dirichlet g.f. zeta(s-1)*zeta(s-2)/(zeta(2s-2)*zeta(s)). - R. J. Mathar, Feb 27 2011 Sum_{k=1..n} a(k) ~ 5*n^3 / (Pi^2 * Zeta(3)). - Vaclav Kotesovec, Jan 11 2019 EXAMPLE a(4) = 18 = (0, -1, 0, 1) dot (1, 6, 12, 24), where (0, -1 0, 1) = row 4 of A054525 and A000082 = (1, 6, 12, 24, 30, 72,...). MAPLE with (numtheory): a:= n-> add (k^2* mul(1+1/p, p=factorset(k)) *mobius (n/k), k=divisors(n)): seq (a(n), n=1..60); # Alois P. Heinz, Aug 28 2008 MATHEMATICA a[n_] := Sum[ k^2*Product[ 1+1/p, {p, FactorInteger[k][[All, 1]]}]* MoebiusMu[n/k], {k, Divisors[n]}] - MoebiusMu[n]; Table[a[n], {n, 1, 50}] (* Jean-François Alcover, Sep 03 2012, after Alois P. Heinz *) CROSSREFS Cf. A000082. Sequence in context: A080566 A094684 A240438 * A048253 A102174 A140515 Adjacent sequences:  A140694 A140695 A140696 * A140698 A140699 A140700 KEYWORD nonn,easy,mult,changed AUTHOR Gary W. Adamson, May 23 2008 EXTENSIONS Definition corrected by N. J. A. Sloane, Jul 28 2008 More terms from Alois P. Heinz, Aug 28 2008 STATUS approved

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Last modified January 18 16:40 EST 2019. Contains 319271 sequences. (Running on oeis4.)