Question 174
Determine the largest possible non-negative integer $k$ for which there exists a positive integer $n$ with the following property:
$n$ is a perfect square with at least $k+1$ digits, and for every $i \lt k$ the integer obtained by deleting the last $i$ digits from $n$ is a perfect square.
$n$ is a perfect square with at least $k+1$ digits, and for every $i \lt k$ the integer obtained by deleting the last $i$ digits from $n$ is a perfect square.