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 jasong 2007-10-09 05:47

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.

 Kees 2007-10-09 06:20

is this the same as to proof that all numbers are odd ?

 Mr. P-1 2007-10-09 06:21

[QUOTE=jasong;115978]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.[/QUOTE]

All primes except 2 are ODD (i.e., not divisible by 2).

2 is the ODD one out.

 jasong 2007-10-09 06:53

[QUOTE=Mr. P-1;115982]All primes except 2 are ODD (i.e., not divisible by 2).

2 is the ODD one out.[/QUOTE]
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 [b]very odd[/b] prime. Therefore, all primes are odd.

 retina 2007-10-09 07:04

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.

 vimil 2007-11-29 00:00

putting it another way

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

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