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PEN H Problems
27
27
Part of
PEN H Problems
Problems
(1)
H 27
Source:
5/25/2007
Prove that there exist infinitely many positive integers
n
n
n
such that
p
=
n
r
p=nr
p
=
n
r
, where
p
p
p
and
r
r
r
are respectively the semi-perimeter and the inradius of a triangle with integer side lengths.
geometry
perimeter
inradius
modular arithmetic
Diophantine Equations