Primes

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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.

#Primes #Diamond #Diamond7

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
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Comments

This is very true

Jonathan Hsu - 6 years ago

But can it be proved in another way?

Ashwin Padaki - 6 years ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$