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Sieve of Eratosthenes

Another way to generate a list of primes is through the Sieve of Eratosthenes.

Essentially you create a long list of numbers starting at 2.
1. Set p equal to 2.  This is your first prime.
2. Cross out every pth number because they are all divisible by p.
3. The first number after p which hasn't been crossed out is the new prime.
4. Repeat from setup 2.

As an example lets take the number line from 2 to 10.
list = 2, 3, 4, 5, 6, 7, 8, 9, 10
1. p = 2
2. list = 2, 3, 4, 5, 6, 7, 8, 9, 10
3. p = 3
4. goto 2
2. list = 2, 3, 4, 5, 6, 7, 8, 9, 10
3. p = 5
4. goto 2
2. list = 2, 3, 4, 5, 6, 7, 8, 9, 10
3. p = 7
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