Fundamental theorem of arithmetic

Every integer greater than 1 (up to sign) can be written as a product of prime powers in exactly one way, apart from the order of the factors. The formula expresses an integer a as a signed product of distinct primes p_i raised to positive exponents e_i.

a=\pm p_1^{e_1}p_2^{e_2}\cdots p_r^{e_r}

What the symbols mean

a nonzero integer other than 1 and -1
distinct prime numbers
positive integer exponent of the prime p_i
number of distinct prime factors of a

About this formula

  • FieldMathematics
  • TopicNumber theory
  • LevelUniversity
  • Also calledunique prime factorization theorem, unique factorization theorem, FTA, prime factorization theorem, prime factorisation theorem, unique factorisation theorem
  • SourceWikidata Q670235

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