A318325 a(n) = Sum_{d|n} [moebius(n/d) > 0]*(sigma(d)-d).
0, 1, 1, 3, 1, 6, 1, 7, 4, 8, 1, 17, 1, 10, 9, 15, 1, 22, 1, 23, 11, 14, 1, 39, 6, 16, 13, 29, 1, 45, 1, 31, 15, 20, 13, 61, 1, 22, 17, 53, 1, 57, 1, 41, 34, 26, 1, 83, 8, 44, 21, 47, 1, 70, 17, 67, 23, 32, 1, 125, 1, 34, 42, 63, 19, 81, 1, 59, 27, 77, 1, 139, 1, 40, 50, 65, 19, 93, 1, 113, 40, 44, 1, 159, 23, 46, 33, 95, 1, 163, 21
Offset: 1
Keywords
Links
- Antti Karttunen, Table of n, a(n) for n = 1..65537
Programs
-
PARI
A318325(n) = sumdiv(n,d,(1==moebius(n/d))*(sigma(d)-d));