Problem #110 EASY
The Last Digit of 7 to the Power of 7777
Paradox Number Theory Math
Problem Statement
What is the last digit of 7^7777? You are not allowed a calculator. The number 7^7777 has thousands of digits — but finding just the last digit requires only a tiny observation about patterns. Find the last digit, then find the last two digits of 7^7777. Generalise: what is the last digit of 7^n for any n?
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