A347231 - OEIS

A347231

Difference between A344695 [gcd(psi(n),sigma(n))] and its Möbius transform.

0, 1, 1, 3, 1, 6, 1, 1, 4, 8, 1, 10, 1, 10, 9, 3, 1, 9, 1, 16, 11, 14, 1, 6, 6, 16, 1, 22, 1, 42, 1, 1, 15, 20, 13, -5, 1, 22, 17, 8, 1, 54, 1, 34, 21, 26, 1, 10, 8, 13, 21, 40, 1, 6, 17, 10, 23, 32, 1, 54, 1, 34, 29, 3, 19, 78, 1, 52, 27, 74, 1, 9, 1, 40, 19, 58, 19, 90, 1, 16, 4, 44, 1, 74, 23, 46, 33, 14, 1, 48

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

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

FORMULA

a(n) = A344695(n) - A347230(n).

a(n) = -Sum_{d|n, d<n} A008683(n/d) * A344695(d).

PROG

(PARI)

A001615(n) = if(1==n, n, my(f=factor(n)); prod(i=1, #f~, f[i, 1]^f[i, 2] + f[i, 1]^(f[i, 2]-1))); \\ After code in A001615

A344695(n) = gcd(sigma(n), A001615(n));