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Baltic Way
2004 Baltic Way
7
7
Part of
2004 Baltic Way
Problems
(1)
More funny number theory
Source: Baltic Way 2004 Problem 7
11/20/2004
Find all sets
X
X
X
consisting of at least two positive integers such that for every two elements
m
,
n
∈
X
m,n\in X
m
,
n
∈
X
, where
n
>
m
n>m
n
>
m
, there exists an element
k
∈
X
k\in X
k
∈
X
such that
n
=
m
k
2
n=mk^2
n
=
m
k
2
.
ratio
number theory proposed
number theory