A369069 Dirichlet convolution of Liouville's lambda (A008836) with A083345, where A083345(n) = n' / gcd(n,n'), and n' stands for the arithmetic derivative of n, A003415.

0, 1, 1, 0, 1, 3, 1, 3, 1, 5, 1, 0, 1, 7, 6, -1, 1, 2, 1, 0, 8, 11, 1, 8, 1, 13, 0, 0, 1, 14, 1, 6, 12, 17, 10, 0, 1, 19, 14, 14, 1, 20, 1, 0, 5, 23, 1, -3, 1, 2, 18, 0, 1, 0, 14, 20, 20, 29, 1, 0, 1, 31, 7, -3, 16, 32, 1, 0, 24, 34, 1, 5, 1, 37, 3, 0, 16, 38, 1, -5, 4, 41, 1, 0, 20, 43, 30, 32, 1, 9, 18, 0, 32, 47

Offset: 1

Author

Antti Karttunen, Jan 16 2024

Keywords

• sign

Comments

In contrast to A347395, this sequence has also nonpositive values after the initial term. It seems that A342090 gives most of the positions of nonpositive terms here, apart from k = 0, 729, 1458, 3645, 5103, 5832, 7290, ..., etc.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16384

Crossrefs

Cf. A003415, A008836, A083345, A342090.

Cf. also A347395, A369068.

Programs

PARI

A008836(n) = ((-1)^bigomega(n));
A083345(n) = { my(f=factor(n)); numerator(vecsum(vector(#f~, i, f[i, 2]/f[i, 1]))); };
A369069(n) = sumdiv(n,d,A008836(n/d)*A083345(d));

Formula

a(n) = Sum_{d|n} A008836(n/d) * A083345(d).