Question 8
Find the sum of all the positive integers $n$ such that $n^4-4n^3+22n^2-36n+18$ is a perfect square.
(Note: If you think that there are infinitely many positive integer values of $n$ that satisfy the above conditions, enter your answer as “9999”.)
(Note: If you think that there are infinitely many positive integer values of $n$ that satisfy the above conditions, enter your answer as “9999”.)