Number Theory

The study of the integers and their properties.

Parent category: Mathematics

Articles (3)

• Prime Numbers and the Sieve of Eratosthenes
  A prime has exactly two divisors, 1 and itself. Learn why primes never run out, how the ancient Sieve of Eratosthenes finds them, and why they secure the internet.
• Euler's Totient Function
  The function φ(n) counting the integers between 1 and n that are coprime to n, a cornerstone of modular arithmetic and the basis of RSA encryption.
• Fundamental Theorem of Arithmetic
  The theorem that every integer greater than 1 factors uniquely into primes, up to the order of the factors.

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