A300717 - OEIS

A300717

Möbius transform of A003557, n divided by its largest squarefree divisor.

1, 0, 0, 1, 0, 0, 0, 2, 2, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 6, 0, 0, 0, 0, 8, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 18, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 6

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OFFSET

1,8

COMMENTS

Multiplicative because A003557 is. - Andrew Howroyd, Jul 27 2018

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) = Sum_{d|n} A008683(n/d)*A003557(d).

a(n) = A000010(n) - A300718(n).

a(n) = A003557(n) - A300719(n).

Multiplicative with a(p) = 0 and a(p^e) = (p-1)*p^(e-2) for prime p and e>1. - Werner Schulte, Sep 27 2018

Dirichlet convolution with A003958 equals A000010. - Werner Schulte, Sep 28 2018

a(n) = Sum_{d|n} mu(d)*phi(d)*phi(n/d). - Ridouane Oudra, Nov 18 2019

Dirichlet convolution of A000010 and A097945. - R. J. Mathar, Jun 02 2020

From Richard L. Ollerton, May 07 2021: (Start)

a(n) = Sum_{k=1..n} phi(gcd(n,k))*mu(gcd(n,k)).

a(n) = Sum_{k=1..n} phi(gcd(n,k))*mu(n/gcd(n,k)). (End)

MAPLE

with(numtheory): A003557 := n -> n/ilcm(op(numtheory[factorset](n))):

seq(add(mobius(d)*A003557(n/d), d in divisors(n)), n=1..100); # Ridouane Oudra, Nov 18 2019

MATHEMATICA

Table[DivisorSum[n, MoebiusMu[#] EulerPhi[#] EulerPhi[n/#] &], {n, 108}] (* Michael De Vlieger, Nov 18 2019 *)

f[p_, e_] := If[e == 1, 0, (p - 1)*p^(e - 2)]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Dec 06 2022 *)

PROG

(PARI)

A003557(n) = { my(f=factor(n)); for (i=1, #f~, f[i, 2] = max(0, f[i, 2]-1)); factorback(f); }; \\ From A003557

A300717(n) = sumdiv(n, d, moebius(n/d)*A003557(d));

(PARI) a(n) = {my(f = factor(n)); prod(i = 1, #f~, if(f[i, 2] == 1, 0, (f[i, 1] - 1)*f[i, 1]^(f[i, 2] - 2))); } \\ Amiram Eldar, Dec 06 2022

CROSSREFS

Cf. A000010, A008683, A003557, A300718, A300719, A003958.

Sequence in context: A240066 A240067 A374248 * A191928 A359887 A033148

Adjacent sequences: A300714 A300715 A300716 * A300718 A300719 A300720

KEYWORD

nonn,mult

AUTHOR

Antti Karttunen, Mar 11 2018

STATUS

approved