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MathLinks Contest 6th
3.1
0631 number theory 6th edition Round 3 p1
0631 number theory 6th edition Round 3 p1
Source:
May 3, 2021
number theory
6th edition
Problem Statement
For each positive integer
n
n
n
let
τ
(
n
)
\tau (n)
τ
(
n
)
be the sum of divisors of
n
n
n
. Find all positive integers
k
k
k
for which
τ
(
k
n
−
1
)
≡
0
\tau (kn - 1) \equiv 0
τ
(
kn
−
1
)
≡
0
(mod
k
k
k
) for all positive integers
n
n
n
.
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