A328310 a(n) = A051903(A003415(n)) - A051903(n).

-1, -1, 0, -1, 0, -1, -1, -1, 0, -1, 2, -1, 1, 2, 1, -1, -1, -1, 1, 0, 0, -1, -1, -1, 0, 0, 3, -1, 0, -1, -1, 0, 0, 1, 0, -1, 0, 3, -1, -1, 0, -1, 2, -1, 1, -1, 0, -1, 0, 1, 1, -1, 1, 3, -1, 0, 0, -1, 0, -1, 0, -1, 0, 1, 0, -1, 1, 0, 0, -1, -1, -1, 0, -1, 2, 1, 0, -1, 0, -1, 0, -1, 0, 0, 1, 4, -1, -1, -1, 1, 3, 0, 1, 2

Offset: 2

Author

Antti Karttunen, Oct 13 2019

Keywords

• sign

Links

• Antti Karttunen, Table of n, a(n) for n = 2..20000

Crossrefs

Cf. A003415, A051903, A328320, A328321.

One less than A328311.

Programs

PARI

A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A051903(n) = if((1==n),0,vecmax(factor(n)[, 2]));
A328310(n) = (A051903(A003415(n)) - A051903(n));

Formula

a(n) = A051903(A003415(n)) - A051903(n).

a(n) = A328311(n) - 1.