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 A128391 A054523^24 * A000594. 2
 1, 0, 300, -1724, 4926, 0, -16600, 44600, -100299, 0, 534852, -517200, -577450, 0, 1477800, 2486626, -6905550, 0, 10661852, -8492424, -4980000, 0, 18643800, 13380000, -25030649, 0, -78396200, 28618400, 128407302, 0, -52842448, -150834520, 160455600, 0, -81771600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Conjecture: Given A054523^k, k = any positive integer, "zero" appears only in the sequence A018391 (k=24). Each application of A054523 corresponds to the Dirichlet convolution of A000010 with the sequence on the right. Since both A000594 and A000010 are multiplicative, the resulting sequence will also be multiplicative. - Andrew Howroyd, Aug 03 2018 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1000 FORMULA A054523^24 as an infinite lower triangular matrix * A000594. MATHEMATICA nmax = 40; T[n_, k_] := If[Divisible[n, k], EulerPhi[n/k], 0]; T[1, 1] = 1; M = Table[T[n, k], {n, 1, nmax}, {k, 1, nmax}]; MatrixPower[M, 24].RamanujanTau[Range[nmax]] (* Jean-François Alcover, Sep 20 2019 *) PROG (PARI) seq(n, k=24)={my(u=vector(n, n, eulerphi(n)), v=vector(n, n, ramanujantau(n))); for(i=1, k, v=dirmul(u, v)); v} \\ Andrew Howroyd, Aug 03 2018 CROSSREFS Cf. A000010, A000594, A054523, A128378, A128379, A128380, A128381, A128392. Sequence in context: A054026 A237773 A188252 * A328132 A234412 A234406 Adjacent sequences: A128388 A128389 A128390 * A128392 A128393 A128394 KEYWORD sign,mult AUTHOR Gary W. Adamson, Feb 28 2007 EXTENSIONS a(7) corrected and terms a(11) and beyond from Andrew Howroyd, Aug 03 2018 STATUS approved

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Last modified September 22 04:32 EDT 2023. Contains 365503 sequences. (Running on oeis4.)