Finding a prime number after a given number

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Published on 2010-03-18T08:44:36Z Indexed on 2010/03/19 5:11 UTC
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primes

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algorithms

How can I find the least prime number greater than a given number? For example, given 4, I need 5; given 7, I need 11.

I would like to know some ideas on best algorithms to do this. One method that I thought of was generate primes numbers through the Sieve of Eratosthenes, and then find the prime after the given number.

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