SOLUTION: What's the smallest prime p such that 2^p -1 is not prime?

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Question 973803: What's the smallest prime p such that 2^p -1 is not prime?
Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What's the smallest prime p such that 2^p -1 is not prime?
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Is the exponent p ?
Or p-1 ?
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Parentheses are free, use some.
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The other tutor (Edwin) is wrong. Not the 1st time.
It could be 2%5Ep+-+1 or 2%5E%28p-1%29
How can I be wrong when I only asked for clarification?
We should not have to figure out what you mean, even if it's obvious.
Making what you want to do clear is part of knowing what you're doing.
Edwin is an asshole.
He knows a lot, but he's an asshole.
He's the only tutor on the site that makes disparaging remarks about the other tutors (up until now).
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He could have submitted his answer without mentioning the "other tutor," but he apparently needs something to feel superior about (even if it's not real).

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
2^p-1  means 2%5Ep-1, no parentheses needs. The other tutor is wrong.]

The smallest prime p such that 2^p - 1 is composite. 
Let's try to find it.  Hope it's not too large.

2%5E2-1%22%22=%22%224-1%22%22=%22%223matrix%281%2C3%2Cwhich%2Cis%2C%22prime.%22%29
2%5E3-1%22%22=%22%228-1%22%22=%22%227matrix%281%2C3%2Cwhich%2Cis%2C%22prime.%22%29
2%5E5-1%22%22=%22%2232-1%22%22=%22%2231matrix%281%2C3%2Cwhich%2Cis%2C%22prime.%22%29
2%5E7-1%22%22=%22%22128-1%22%22=%22%22127matrix%281%2C3%2Cwhich%2Cis%2C%22prime.%22%29
2%5E11-1%22%22=%22%222048-1%22%22=%22%222047matrix%281%2C3%2Cwhich%2Cis%2C%2223%D789.%22%29

That's it! Answer = 11
 
Edwin