1 **2** **3** 4 **5** 6

**7** 8 9 10 **11** 12

**13** 14 15 16 **17** 18

I would like to bring something up that I discovered in 5th grade. All primes other than 2 and 3 can be expressed as *6n + 1* or *6n - 1*. I think I know why, but I would like to see some other ideas...

**My Ideas**

*6n*,*6n + 2*,*6n - 2*are all even.*6n + 3*is a multiple of 3.*6n + 1*and*6n - 1*are the only remaining possibilities.

## Comments

Sort by:

TopNewestThis is very true – Jonathan Hsu · 1 year, 4 months ago

Log in to reply

– Ashwin Padaki · 1 year, 4 months ago

But can it be proved in another way?Log in to reply