A333783 a(n) = sigma(n) - A332993(n).

0, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 6, 0, 2, 3, 0, 0, 8, 0, 6, 3, 2, 0, 14, 0, 2, 0, 6, 0, 21, 0, 0, 3, 2, 5, 24, 0, 2, 3, 14, 0, 25, 0, 6, 12, 2, 0, 30, 0, 12, 3, 6, 0, 26, 5, 14, 3, 2, 0, 57, 0, 2, 12, 0, 5, 33, 0, 6, 3, 31, 0, 56, 0, 2, 18, 6, 7, 37, 0, 30, 0, 2, 0, 69, 5, 2, 3, 14, 0, 78, 7, 6, 3, 2, 5, 62, 0, 16, 12

Offset: 1

Author

Antti Karttunen, Apr 05 2020

Keywords

• nonn
• look

Comments

Sum of all other divisors of n, except those divisors that can be obtained by repeatedly taking the largest proper divisor (of previous such divisor, starting from n), up to and including the terminal 1.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16384
• Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203, A000961 (positions of zeros), A001065, A006022, A032742, A332993, A333784, A333791.

Programs

PARI

A332993(n) = if(1==n,n,n + A332993(n/vecmin(factor(n)[,1])));
A333783(n) = (sigma(n) - A332993(n));

Formula

a(n) = A000203(n) - A332993(n).

a(n) = A001065(n) - A006022(n).

a(n) = A333784(n) - A333791(n).