Problem of the Week 3-28-19: Functional Equation for Irrationals [Functional Equations]

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Advanced Knowledge Problem of the Week 3-26-19: Functional Equation for Rationals [Functional Equations]

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Problem of the Week 3-21-19: Divisible by 2009 [Number Theory]

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Advanced Knowledge Problem of the Week 3-19-19: A Countable Set [Set Theory]

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Problem of the Week 3-14-19: A Sequence of Not Square Integers [Number Theory]

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Advanced Knowledge Problem of the Week 3-12-19: A Sufficient Condition for a Tree [Graph Theory]

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