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Let
be a positive integer, and let
denote the sum of the positive divisors of
. Prove that the
smallest positive integer relatively prime to
is at least
, and determine for which
equality holds.
Proposed by Ashwin Sah







Proposed by Ashwin Sah
This post has been edited 3 times. Last edited by 62861, Dec 11, 2017, 5:07 PM
Reason: proposer
Reason: proposer