Erdős Problem 1052 #
Reference: erdosproblems.com/1052
A proper unitary divisor of $n$ is a divisor $d$ of $n$ such that $d$ is coprime to $n/d$, and $d < n$.
Equations
- Erdos1052.properUnitaryDivisors n = {d ∈ Finset.Ico 1 n | d ∣ n ∧ d.Coprime (n / d)}
Instances For
A number $n > 0$ is a unitary perfect number if it is the sum of its proper unitary divisors.
Equations
- Erdos1052.IsUnitaryPerfect n = (∑ i ∈ Erdos1052.properUnitaryDivisors n, i = n ∧ 0 < n)
Instances For
Are there only finitely many unitary perfect numbers?
All unitary perfect numbers are even.
theorem
Erdos1052.isUnitaryPerfect_146361946186458562560000 :
IsUnitaryPerfect 146361946186458562560000