A305791 Dirichlet convolution of A175851 with itself.

1, 2, 2, 5, 2, 6, 2, 8, 7, 10, 2, 12, 2, 6, 8, 16, 2, 14, 2, 16, 8, 10, 2, 20, 7, 10, 16, 20, 2, 22, 2, 20, 8, 10, 12, 36, 2, 6, 8, 32, 2, 18, 2, 16, 18, 10, 2, 32, 7, 22, 12, 24, 2, 30, 8, 32, 12, 14, 2, 44, 2, 6, 18, 32, 12, 30, 2, 16, 8, 30, 2, 48, 2, 6, 18, 16, 12, 30, 2, 44, 25, 10, 2, 44, 8, 10, 12, 36, 2, 54, 8, 20, 12, 14, 16, 56, 2

Offset: 1

Author

Antti Karttunen, Jun 13 2018

Keywords

• nonn

Links

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

Crossrefs

Cf. A175851.

Cf. also A305796, A305797, A305798, A305799.

Programs

PARI

A175851(n) = if(1==n,n,1 + n - precprime(n));
A305791(n) = sumdiv(n,d,A175851(d)*A175851(n/d));

Formula

a(n) = Sum_{d|n} A175851(d)*A175851(n/d).