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### Twin Primes

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Date: 5/16/96 at 14:30:13
From: The Green Vale School
Subject: Twin Primes

Is there an infinite number of twin primes?
```

```
Date: 5/16/96 at 20:53:25
From: Doctor Ken
Subject: Re: Twin Primes

Hello!

One of my fellow math doctors, Doctor Jodi, found this information
about twin primes:

The world's largest known pair of twin primes is

190116 x 3003 x 10^5120 - 1 and 190116 x 3003 x 10^5120 +1

These are numbers of the form n - 1 and n + 1, both of which are
primes. Other examples are 17 and 19, and 101 and 103.

The largest pair, above, have 5129 digits each. They were discovered
on 9 October 1995.  It is thought that there are infinitely many
pairs of twin primes, but nobody has been able to prove this.

Jodi found this information on a web site, and you can visit it too if
you want to.  The URL for it is

http://www.utm.edu/research/primes/largest.html

Here's a question for you.  How many _triplet_ primes are there, three
odd numbers in a row (for instance, 3, 5, 7) such that each one is a
prime?  Can you prove your answer?

-Doctor Ken,  The Math Forum
Check out our web site!  http://mathforum.org/dr.math/
```
Associated Topics:
Middle School Prime Numbers

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