Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: 7!= 2*5! * 2*3! *7
Replies: 14   Last Post: Jun 14, 2013 10:35 PM

 Messages: [ Previous | Next ]
 Brian Chandler Posts: 1,899 Registered: 12/6/04
Re: 7!= 2*5! * 2*3! *7
Posted: Jun 11, 2013 12:12 PM

JT wrote:
> Ooops got it wrong there, *2 of course
> 13!=2*11!*2*9!*2*7!*2*5!*2*3!*13
>
> Try me, how can you use this?

Well, you can divide both sides by 13 getting:

12! = 2*11!* 2*9!*2*7!*2*5!*2*3!

And if this isn't enough: divide by 12:

11! = 2*11!* 2*9!*2*7!*2*5!

Then 1 = 2*2*9!*2*7!*2*5!

So even allowing for experimental error, we get 1 > 2^18

Which means 2 is a lot smaller than previously thought.

Brian Chandler

Date Subject Author
6/11/13 JT
6/11/13 JT
6/11/13 JT
6/11/13 Dirk Van de moortel
6/11/13 JT
6/11/13 Brian Chandler
6/11/13 JT
6/11/13 JT
6/11/13 JT
6/11/13 Richard Tobin
6/12/13 JT
6/12/13 JT
6/12/13 JT
6/11/13 Richard Tobin