Erdős Problem 1052 #
Reference: erdosproblems.com/1052
A proper unitary divisor of $n$ is $d \mid n$ such that $(d, n/d) = 1$ other than $n$.
Equations
- Erdos1052.properUnitaryDivisors n = Finset.filter (fun (d : ℕ) => d ∣ n ∧ d.Coprime (n / d)) (Finset.Ico 1 n)
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