12.2.46 Number Theory
Condition: how many integers in the sequence \ (\ frac {1 \ cdot a} {b}, \ frac {2 \ cdot a} {b}, \ ldots, \ frac {b \ cdot a} {b} \), where \ in \ in \ mathb (n} \).
A Huge Number of Interesting Olympiad Problems in Number Theory, and Its Various Section.