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2019 JBMO Shortlist
N7
N7
Part of
2019 JBMO Shortlist
Problems
(1)
JBMO Shortlist 2019 N7
Source:
9/12/2020
Find all perfect squares
n
n
n
such that if the positive integer
a
≥
15
a\ge 15
a
≥
15
is some divisor
n
n
n
then
a
+
15
a+15
a
+
15
is a prime power.Proposed by Saudi Arabia
number theory