sigma(phi(n)) = rad(n), where phi(n)= Euler totient function, sigma(n)= sum of divisors of n, rad(n)= product of primes that divide n.
A173146
sigma(phi(n)) = rad(n), where phi(n)= Euler totient function, sigma(n)= sum of divisors of n, rad(n)= product of primes that divide n.
Terms
- a(0) =3a(1) =15a(2) =255a(3) =2418a(4) =65535a(5) =110771178a(6) =4294967295
External references
- oeis: A173146