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Math
Advanced Topics
Intro to Number Theory
Integers Modulo N, in Detail
Division, Inverses, and Linear Congruences Modulo N
Common Residue Systems, and Significance
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Problems
1
Petya gave Vasya a number puzzle. Petya chose a digit XXX and said, "I am thinking of a three digit number that is divisible by 11. The hundreds digit is XXX and the tens digit …
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