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5
5
Part of
PEN S Problems
Problems
(1)
S 5
Source:
5/25/2007
Suppose that both
x
3
−
x
x^{3}-x
x
3
−
x
and
x
4
−
x
x^{4}-x
x
4
−
x
are integers for some real number
x
x
x
. Show that
x
x
x
is an integer.
algebra
polynomial
number theory
greatest common divisor
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