how do you find this to be a prime number or not..... 222221

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marty.frmn
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how do you find this to be a prime number or not..... 222221

Postby marty.frmn » Thu Oct 22, 2009 7:17 am

how do you find this to be a prime number or not..... 222221????

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stapel_eliz
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Postby stapel_eliz » Thu Oct 22, 2009 1:33 pm

Divide by primes. If something no larger than the square root of the number "fits", it's composite. Otherwise, it's prime. :wink:


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