Advanced Knowledge Problem of the Week 7-5-18: Infinite Squares and Euler's Totient Function [Number Theory]

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Problem of the Week 7-3-18: Invariant Sums of Digits [Number Theory]

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Advanced Knowledge Problem of the Week 6-28-18: Conjugates of a Subgroup [Group Theory]

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Problem of the Week 6-26-18: Integers and Quartics [Number Theory]

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Ramanujan's Sum Identity

A fascinating result due to Ramanujan!

Advanced Knowledge Problem of the Week 6-21-18: A Problem involving Connected Sets [Topology]

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