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P 20
Source:
May 25, 2007
Additive Number Theory
Problem Statement
If an integer
n
n
n
is such that
7
n
7n
7
n
is the form
a
2
+
3
b
2
a^2 +3b^2
a
2
+
3
b
2
, prove that
n
n
n
is also of that form.
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