Question 3
(USS 3) Find all positive integers $n$ such that
$$n=d_6^2+d_7^2-1,$$
where $1=d_1\lt d_2\lt \cdots\lt d_k=n$ are all positive divisors of the number $n$.
$$n=d_6^2+d_7^2-1,$$
where $1=d_1\lt d_2\lt \cdots\lt d_k=n$ are all positive divisors of the number $n$.