Definition of Mersenne number in English:

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Mersenne number

Pronunciation: /məːˈsɛn/


A number of the form 2p−1, where p is a prime number. Such a number which is itself prime is also called a Mersenne prime.
Example sentences
  • Expressed in the form 2 p - 1, where the exponent p is itself prime, Mersenne numbers have characteristics that make it relatively easy to determine whether a candidate is prime.
  • Written in the form 2 p - 1, where the exponent p is a prime number, Mersenne numbers hold a special place in the never-ending pursuit of larger and larger primes.
  • One must be the Lucas Lehmer primality test which uses the Fermat congruence, and in particular his application to testing whether a Mersenne number was prime.


Late 19th century: named after Marin Mersenne (1588–1648), French mathematician.

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