When the Sum of Aliquots Divides the Totient
نویسندگان
چکیده
Let φ(·) be the Euler function and let σ(·) be the sum-of-divisors function. In this note, we bound the number of positive integers n x with the property that s(n) = σ(n)− n divides φ(n).
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تاریخ انتشار 2007