How to prove that all odd numbers are prime

"It was mentioned on CNN that the new prime number discovered recently is four times bigger than the previous record."    — John Blasik

This was compiled from different postings to rec.humor.
Hmmm, by the way, did you know that 1 is not prime ?

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Odd primes

How to prove that all odd numbers are prime ?
Well, this problem has different solutions whether you are a:
Mathematician:
3 is prime, 5 is prime, 7 is prime, and by induction we have that all the odd integers are prime.
Physicist:
3 is prime, 5 is prime, 7 is prime, 9 is an experimental error...
Engineer:
3 is prime, 5 is prime, 7 is prime, 9 is prime...
Chemist:
3 is prime, 5 is prime... hey, let's publish!
Modern physicist using renormalization:
3 is prime, 5 is prime, 7 is prime, 9 is ... 9/3 is prime, 11 is prime, 13 is prime, 15 is ... 15/3 is prime, 17 is prime, 19 is prime, 21 is ... 21/3 is prime...
Quantum Physicist:
All numbers are equally prime and non-prime until observed.
Professor:
3 is prime, 5 is prime, 7 is prime, and the rest are left as an exercise for the student.

[IshangoBone.gif]
The Ishango bones, maybe the first compilation of prime numbers ever.

Left: The Ishango bones, maybe the first compilation of prime numbers ever.

Confused Undergraduate:
Let p be any prime number larger than 2. Then p is not divisible by 2, so p is odd. QED
Measure nontheorist:
There are exactly as many odd numbers as primes (Euclid, Cantor), and exactly one even prime (namely 2), so there must be exactly one odd nonprime (namely 1).
Cosmologist:
3 is prime, yes it is true....
Computer Scientist:
10 is prime, 11 is prime, 101 is prime...
Programmer:
3 is prime, 5 is prime, 7 is prime, 9 will be fixed in the next release, ...
C programmer:
03 is prime, 05 is prime, 07 is prime, 09 is really 011 which everyone knows is prime, ...
BASIC programmer:
What's a prime?
COBOL programmer:
What's an odd number?
Windows programmer:
3 is prime. Wait...
Mac programmer:
Now why would anyone want to know about that? That's not user friendly. You don't worry about it, we'll take care of it for you.
Bill Gates:
1. No one will ever need any more than 3.
From the excellent XKCD webcomic.
ZX-81 Computer Programmer:
3 is prime, Out of Memory.
Pentium owner:
3 is prime, 5 is prime, 7 is prime, 8.9999978 is prime...
GNU programmer:
% prime
usage: prime [-nV] [--quiet] [--silent] [--version] [-e script] --catenate --concatenate | c --create | d --diff --compare | r --append | t --list | u --update | x -extract --get [ --atime-preserve ] [ -b, --block-size N ] [ -B, --read-full-blocks ] [ -C, --directory DIR ] [--checkpoint ] [ -f, --file [HOSTNAME:]F ] [ --force-local ] [ -F, --info-script F --new-volume-script F ] [-G, --incremental ] [ -g, --listed-incremental F ] [ -h, --dereference ] [ -i, --ignore-zeros ] [ --ignore-failed-read ] [ -k, --keep-old-files ] [ -K, --starting-file F ] [ -l, --one-file-system ] [ -L, --tape-length N ] [ -m, --modification-time ] [ -M, --multi-volume ] [ -N, --after-date DATE, --newer DATE ] [ -o, --old-archive, --portability ] [ -O, --to-stdout ] [ -p, --same-permissions, --preserve-permissions ] [ -P, --absolute-paths ] [ --preserve ] [ -R, --record-number ] [ [-f script-file] [--expression=script] [--file=script-file] [file...]
prime: you must specify exactly one of the r, c, t, x, or d options
For more information, type "prime --help''
Unix programmer:
3 is prime, 5 is prime, 7 is prime, ...
Segmentation fault, Core dumped.
Computer programmer:
3 is prime, 5 is prime, 7 is prime, 9 is prime, 9 is prime, 9 is prime, 9 is ...
Oops, let's try that again:
3 is prime, 5 is prime, 7 is prime, 9 is ... 3 is prime, 5 is prime, 7 is prime, 9 is ... 3 is ...
Um, right. Okay, how about this:
3 is not prime, 5 is not prime, 7 is not prime, 9 is not prime...
So much for the beta releases. Ship this:
3 is prime, 5 is prime, 7 is prime, 9 is a feature, 11 is prime...
and put on the cover "More prime numbers than anyone else in the industry !"
Coming soon:
3 is a prime, 4 is a feature, 5 is a prime, 6 is a feature, 7 is a prime, 8 is not yet implemented, 9 is our backwards compatibility module, ...
Computational linguist:
3 is an odd prime, 5 is an odd prime, 7 is an odd prime, 9 is a very odd prime, ...
Software tech support operator:
Well, we haven't had any reports of composite odd numbers... do you have the latest version of ZFC?
Minesweeper addict
1 is green, 2 is blue, 3 is orange, 4 is red...
Logician:
Hypothesis: All odd numbers are prime
Proof:
  1. If a proof exists, then the hypothesis must be true
  2. The proof exists; you're reading it now.
From 1 and 2 follows that all odd numbers are prime
Linguist:
3 is prime, 5 is prime, 7 is prime, 9 aaah. I can make 9 a prime.
Philosopher:
Why don't we just call all the odd numbers prime and call all the prime numbers odd, that way all the odd numbers would be prime
Philosopher (2):
3 is prime. Hum, that's an interesting statement, I'll get one of my research students to look into that.
Economist:
Assume 9 is prime...
Economist (2):
2 is a prime, 4 is a prime.
Economist (3):
2 is even, 4 is even, 6 is even...
Economist (4):
3 is prime, 5 is prime, 7 is prime, 9 is not prime. Look, the prime rate is dropping.
Statistician:
100% of the sample 5, 13, 37, 41 and 53 is prime, so all odd numbers must be prime.
Mechanical Statistician:
3 is prime, 5 is prime, 7 is prime, 9 is an outlier, 11 is prime, 13 is prime...
English major:
What's a prime number ?
Politician:
What's a number ?
Politician (2):
It depends on what the meaning of is is.
Philosophy major:
What is ?
Athletic scholarship:
What !?
Mid-level manager:
3 is prime, 5 is prime, 7 is prime, 9 is... Who can I delegate this to ?
Lawyer:
3 is prime, 5 is prime, 7 is prime, although there appears to be prima facie evidence that 9 is not prime, there exists substantial precedent to indicate that nine should be considered prime. The following brief presents the case for nine's primeness ...
Salesman:
3 is prime, 5 is prime, 7 is prime, and with 9 you get five excellent primes for the price of three !
Anthropologist:
Prime or not, every number is unique. Take 9 for example...
Liberal:
The fact that nine is not prime indicates a deprived cultural environment which can only be remedied by a federally funded cultural enrichment program.
Bush:
What's nine got against being prime? I'll bet it won't allow the pledge of allegiance to be said in our schools either.
Nixon:
Put nine on the enemies list. I'm gonna get that number.
New Yorker:
3 is prime, 5 is prime, 7 is prime, 9 is ... NONE OF YOUR DAMN BUSINESS!
rec.humor poster:
3 is prime, 3 is prime, 3 is prime, 3 is prime

"You know what seems odd to me ? Numbers that aren't divisible by two."    — Michael Wolf.
"I don't get even, I get odder."