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### Square and Composite Numbers

```
Date: 9/5/96 at 19:39:49
From: Anonymous
Subject: Square and Composite Numbers

Is it possible for a number to be a square number and a composite
number?
```

```
Date: 9/6/96 at 19:52:10
From: Doctor Tom
Subject: Re: Square and Composite Numbers

Sure.

A square number is any number that's obtained by multiplying a number
by itself. For example, here are the first few square numbers:

1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121

A composite number is any number that has more than one factor
(other than 1 and itself). The first few non-composite numbers are:

1, 2, 3, 5, 7, 11, 13, 17, 19, 23

The only numbers that divide evenly into them are 1 and themself.

12 is composite, since 2, 3, 4, and 6 divide it evenly (in addition,
of course, to 1 and 12).

So EVERY square except 0 and 1 are composite.  For example, 25 = 5*5,
so we know that 5 divides it evenly.  121 = 11*11, so we know 11
divides it evenly, and so on.

-Doctor Tom,  The Math Forum
Check out our web site!  http://mathforum.org/dr.math/
```
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