Prime Numbers - Sieve of Eratosthenes

Prime Numbers

Sieve of Eratosthenes - finding the prime numbers between 1 and 100

In the left column, click the "Remove Multiples of ..." comments along the left column. When you are done, you will be left with the primes between 1 and 100. You will be left with numbers than can only be factored to 1 x <the number>. As you do play with this, do you see anything curious about how numbers vanish and what numbers are left?

Remove multiples of 2, except 2.

  2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20

Remove multiples of 3, except 3.

21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40

Remove multiples of 5, except 5.

41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60

Remove multiples of 7, except 7.

61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80

Remove multiples of 11, except 11.

81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100