login
Dirichlet convolution of A175851 with itself.
6

%I #5 Jun 13 2018 09:12:28

%S 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,

%T 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,

%U 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

%N Dirichlet convolution of A175851 with itself.

%H Antti Karttunen, <a href="/A305791/b305791.txt">Table of n, a(n) for n = 1..65537</a>

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

%o (PARI)

%o A175851(n) = if(1==n,n,1 + n - precprime(n));

%o A305791(n) = sumdiv(n,d,A175851(d)*A175851(n/d));

%Y Cf. A175851.

%Y Cf. also A305796, A305797, A305798, A305799.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jun 13 2018