OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (calculated using data from Jud McCranie, terms 1..500 from Donovan Johnson)
EXAMPLE
n=56: tau(56)=8, sigma(56)=120, phi(56)=24, q1=120/24=5 for balancedness, q2=56/8=7 for refactorability.
MATHEMATICA
Do[s=DivisorSigma[1, n]/EulerPhi[n]; If[ !IntegerQ[s]&&!PrimeQ[n], Print[n]], {n, 1, 256}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Dec 04 2002
STATUS
approved