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2019 AMC 10A Question 15

AMC10 · 2019 AMC 10A

Question 15

A sequence of numbers is defined recursively by $a_1 = 1,$ $a_2 = \frac{3}{7},$ and $$
a_n=\dfrac{a_{n-2} \cdot a_{n-1}}{2a_{n-2} - a_{n-1}}
$$ for all $n \geq 3.$ Then $a_{2019}$ can be written as $\frac{p}{q},$ where $p$ and $q$ are relatively prime positive integers. What is $p+q ?$
  1. $2020$
  2. $4039$
  3. $6057$
  4. $6061$
  5. $8078$