Erastothene’s sieve interactive

Prime numbers are special numbers with exactly two factors. Erastothene’s sieve is a way of finding those prime numbers by removing the multiples of numbers. You can see them above. Prime factor trees are useful to show the numbers that a whole number can be reduced to.

Hello,

You’ve got my math blog, Math Concepts Explained, listed in your sidebar blogroll. Would you mind including my new and improved math site there as well? It is “The Numerist” at http://www.thenumerist.com. Thanks again for supporting my site!

Cheers,

Shaun