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### Is Zero Prime or Composite?

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Date: 10/23/95 at 19:31:44
From: Andrew Cotton

Hi,

I am fairly new to teaching 7th grade math.  We have been studying
prime and composite numbers.  I have had little difficulty explaining
that "2" is a prime number and that "1" is neither prime nor composite.
and have not been successful at finding a solution.  So, is "0" prime,
composite, or neither?

Thanks!

Andy Cotton
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Date: 11/5/95 at 15:43:30
From: Doctor Jeremy
Subject: Re: 7th Grade Math Question

It is neither.  It is not prime - lots of other numbers divide into it.
(They all do, except for zero itself).  But it is not composite - the
only way you could get zero by multiplying primes together is if
one of the primes were zero, which isn't the case.

Often when defining prime and composite numbers, the fact that the
number must be greater than one is part of the definition.

-Doctor Jeremy,  The Geometry Forum

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