OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
3: {2}
4: {1,1}
5: {3}
7: {4}
8: {1,1,1}
9: {2,2}
11: {5}
13: {6}
16: {1,1,1,1}
17: {7}
19: {8}
23: {9}
25: {3,3}
27: {2,2,2}
29: {10}
30: {1,2,3}
31: {11}
32: {1,1,1,1,1}
MATHEMATICA
Select[Range[100], DivisorSigma[0, #]!=PrimeOmega[#]*PrimeNu[#]&]
PROG
(PARI) is(k) = {my(f = factor(k)); numdiv(f) != omega(f) * bigomega(f); } \\ Amiram Eldar, Jul 28 2024
CROSSREFS
Nonzeros of A328958.
The complement is A328956.
Prime signature is A124010.
Omega-sequence is A323023.
omega(n) * Omega(n) is A113901(n).
(Omega(n) - 1) * omega(n) is A307409(n).
sigma_0(n) - Omega(n) * omega(n) is A328958(n).
sigma_0(n) - 2 - (Omega(n) - 1) * omega(n) is A328959(n).
KEYWORD
nonn
AUTHOR
Gus Wiseman, Nov 01 2019
STATUS
approved