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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Problem of the Week 3-7-19: Is this expression an integer? [Number Theory]

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New Video Series on Graph Theory

This series describes some basic theories in graph theory. We go over some basic definitions in graph theory, what isomorphisms are and what being connected means, eulerian, hamiltonian, Cayley and planar graphs, tournaments and Ramsey numbers. We prove some basic theorems for these various different types of graphs, and prove the existence of the Ramsey number for complete graphs. We give a necessary and sufficient condition for a graph to be eulerian, a sufficient condition to be hamiltonian, and a necessary condition fo a planar graph.

Advanced Knowledge Problem of the Week 3-5-19: Periodic Decimal Expansions [Number Theory]

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