sieve of Eratosthenes

noun phrase

sieve of Er·​a·​tos·​the·​nes -ˌer-ə-ˈtäs-thə-ˌnēz How to pronounce sieve of Eratosthenes (audio)
: a procedure for finding prime numbers that involves writing down the odd numbers from 2 up in succession and crossing out every third number after 3, every fifth after 5 including those already crossed out, every seventh after 7, and so on with the numbers that are never crossed out being prime

Word History

First Known Use

1803, in the meaning defined above

Time Traveler
The first known use of sieve of Eratosthenes was in 1803

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Cite this Entry

“Sieve of Eratosthenes.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sieve%20of%20Eratosthenes. Accessed 27 Feb. 2025.

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