PotW: An Equation with No Integer Solutions [Number Theory]

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PotW: An Equation with Prime Numbers [Number Theory]

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Problem of the Week 5-23-19: Looking for Integer Solutions [Number Theory]

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Problem of the Week 5-16-19: Sums of Squares and 7 [Number Theory]

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Advanced Knowledge Problem of the Week 4-30-19: Primitive Root and -1 [Number Theory]

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Problem of the Week 4-25-19: Divisors of a Power of 10 [Number Theory]

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

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

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

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Advanced Knowledge Problem of the Week 2-19-19: Prime Divisor of Numerator [Algebra]

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Problem of the Week 2-14-19: Finding a Positive Integer Solution [Number Theory]

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New Video Series on Number Theory

Prime Phyllotaxis Spiral

This series is for beginners in Number Theory. The series starts with an introduction to congruences. We review the basic properties of congruences and present the proofs of these properties. Once you become comfortable working with modular arithmetic, we introduce Fermat's Little Theorem and Euler's Theorem. We go over common applications of these theorems, such as solving linear congruences, finding the least positive residue and solving modular inverses. Then, we learn how to solve a set of congruences using the Chinese Remainder Theorem. We finish the series by discussing the order of integers and primitive prime roots.  

Advanced Knowledge Problem of the Week 2-5-19: Sum of Relatively Prime Integers [Number Theory]

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Problem of the Week: 10-18-18: Prove that the Fraction is Irreducible [Number Theory]

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Problem of the Week: 09-06-18: Solving Linear Congruence using Fermat's Little Theorem [Number Theory]

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

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Problem of the Week 6-12-18: Making Polynomials Prime [Number Theory]

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Problem of the Week 5-29-18: Numbers with Certain Divisors [Number Theory]

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