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Old 2007-10-09, 05:47   #1
jasong
 
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"Jason Goatcher"
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Default Odd primes

Puzzle: Prove that all primes, including 2, are odd.

You have to think outside the box for this one. It is possible to prove, although mathematical purists(snobs?) won't like the proof.
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Old 2007-10-09, 06:20   #2
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is this the same as to proof that all numbers are odd ?
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Old 2007-10-09, 06:21   #3
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Quote:
Originally Posted by jasong View Post
Puzzle: Prove that all primes, including 2, are odd.

You have to think outside the box for this one. It is possible to prove, although mathematical purists(snobs?) won't like the proof.
All primes except 2 are ODD (i.e., not divisible by 2).

2 is the ODD one out.
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Old 2007-10-09, 06:53   #4
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Quote:
Originally Posted by Mr. P-1 View Post
All primes except 2 are ODD (i.e., not divisible by 2).

2 is the ODD one out.
Well, I'd phrase it a little differently.

All, primes, except 2, are odd. Out of an infinite number of primes, only 2 is even. This makes 2 a very odd prime. Therefore, all primes are odd.
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Old 2007-10-09, 07:04   #5
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So it's a play on words.

Odd = not even, and
Odd = not normal

All primes are odd but not necessarily odd in the same way.
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Old 2007-11-29, 00:00   #6
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Default putting it another way

All primes are odd but some primes are more odd than others
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