Math Is Fun Forum

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#1 2014-08-25 05:46:38

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
Website

Interesting property of 7!

How many solutions of x! = nPr are there such that n and r are different?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#2 2014-08-25 05:52:52

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Interesting property of 7!

An infinite number. 7 Npr 6 = 7!, 6 Npr 5 = 6! etc.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2014-08-25 09:01:57

Olinguito
Member
Registered: 2014-08-12
Posts: 649

Re: Interesting property of 7!

A more interesting problem is:

For example, 6! = 10 × 9 × 8.

I am still unable to solve it.

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Bassaricyon neblina

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#4 2014-08-25 10:17:38

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Interesting property of 7!

Hi;


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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