Positive Integers n Such That σ ( φ ( n ) ) = σ ( n )
نویسندگان
چکیده
In this paper, we investigate those positive integers n for which the equality σ(φ(n)) = σ(n) holds, where σ is the sum of the divisors function and φ is the Euler function.
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تاریخ انتشار 2008