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## #1 2009-03-08 15:32:50

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

### Prove composite

(This is a problem I made up myself.)

Last edited by JaneFairfax (2009-03-08 15:54:48)

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## #2 2009-03-08 18:59:00

Identity
Member
Registered: 2007-04-18
Posts: 934

### Re: Prove composite

But I don't think that is the solution you were looking for

Last edited by Identity (2009-03-08 19:00:59)

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## #3 2009-03-08 23:43:05

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

### Re: Prove composite

That was indeed part of the soluttion I was looking for. But the proof is not complete yet.

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## #4 2009-03-09 07:59:09

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Prove composite

I did a question similar to this a few days ago. The first part was pretty much Jane's question, but without the k included.

It then followed up by asking you to show that 4[sup]n[/sup] + n[sup]4[/sup] is composite (for n>1).
Any takers?

Why did the vector cross the road?
It wanted to be normal.

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## #5 2009-03-09 09:40:35

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

### Re: Prove composite

Here is the solution to your problem.

http://www.thescienceforum.com/viewtopic.php?t=6344

Now can we please concentrate on my own question here?

Last edited by JaneFairfax (2009-03-09 09:56:38)

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## #6 2009-03-09 09:53:56

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Prove composite

Calm down, I didn't mean to derail the topic. I decided I'd post the new problem because:

- Your problem has pretty much been solved already. The part that's left is considerably easier than the part that's been done.

- Your result is used in a nice proof for my problem, so I thought it'd be a good extension.

Anyway, sorry for upsetting you.
Everyone please focus completely on the original question because that's what this topic is about.

Why did the vector cross the road?
It wanted to be normal.

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## #7 2009-03-09 11:46:14

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

### Re: Prove composite

Thanks.

You would be wrong to suppose my question is almost solved  there is still some work to be done. Identity did not use the condition
, which is a crucial condition. Otherwise you could have
.

Last edited by JaneFairfax (2009-03-09 12:08:00)

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## #8 2009-03-14 03:36:21

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

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## #9 2009-04-17 08:55:12

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

### Re: Prove composite

Hi Jane;

Thanks for providing the solution. Checking out the scienceforum link you provided their is a member that is like you but under another alias. On checking out her profile it leads to the invision forum where you appear as Jane Fairfax.

bobbym

Last edited by bobbym (2009-04-17 08:57:07)

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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## #10 2009-04-17 08:57:57

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

### Re: Prove composite

Well, you could have accessed the forum much more quickly by clicking the Did You Know? link in my signature.

Feel free to join the forum.

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## #11 2009-04-17 17:24:45

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

### Re: Prove composite

Sorry Jane, I was being nosy. Thanks for the invite. I already do a lot of lurking there.
(Hope you did not see the rest of this post before I got a chance to delete it. Stupidly, put my foot in my mouth with that thoughtless comment.)

Last edited by bobbym (2009-04-19 20:30:43)

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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