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
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
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