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2021 LMT Spring
A16
A16
Part of
2021 LMT Spring
Problems
(1)
2021 LMT Spring Division A Problem 16
Source:
10/22/2021
Find the number of ordered pairs
(
a
,
b
)
(a,b)
(
a
,
b
)
of positive integers less than or equal to
20
20
20
such that \gcd(a,b)>1 \text{and} \frac{1}{\gcd(a,b)}+\frac{a+b}{\text{lcm}(a,b)} \geq 1.Proposed by Zachary Perry