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PEN A Problems
42
A 42
A 42
Source:
May 25, 2007
modular arithmetic
Divisibility Theory
pen
Problem Statement
Suppose that
2
n
+
1
2^n +1
2
n
+
1
is an odd prime for some positive integer
n
n
n
. Show that
n
n
n
must be a power of
2
2
2
.
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