Squaring Preserves Digits
Number Theory
Level
3
Consider all 2 digit numbers \(N\) such that the last 2 digits of \(N^2\) are \(N\) itself. What is the sum of all these 2 digit numbers?
Details and assumptions
The number \(12 = 012\) is a 2-digit number, not a 3-digit number.
by
Calvin Lin