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 ixfd64 2003-09-22 20:06

some prime-related trick questions

Bored? Give these tests to your friends! :D

1. Some natural numbers have two factors. Some have three, some have four, and so on. How many have one factor?

2. Before 2[sup]6,972,593[/sup] - 1 was discovered, what was the largest Mersenne prime whose exponent was less than 10 million?

3. Find the factors of the prime number 2[sup]13,466,917[/sup] -1.

4. (This one's sorta dumb.) You want to do some math work with Prime95, MFAC (for double-Mersenne numbers), and Proth.exe (for Proth and other primes), but you only want one program to be running at once. Which do you load first?

1. All of them. Every natural number has at least one factor. Notice how I didn't use the word "exactly"?

2. 2[sup]6,972,593[/sup] - 1. It was always there, even before it is discovered.

3. 1 and 2[sup]13,466,917[/sup] - 1. Notice the word "prime".