00:01
Here i've written out the first 20 numbers.
00:03
Let's begin by crossing out those that we know are not composite.
00:07
Well, one is not composite because it only has one factor, specifically one.
00:11
Two is prime, three is prime.
00:14
However, four is a composite number.
00:17
Five is prime, six is composite.
00:19
We know it's even, so at least has two as a factor.
00:23
Seven is prime.
00:24
Eight, here's another number that is even, so we know it has two.
00:28
Nine has three as a factor, so it's composite number.
00:33
10 is composite...