Originally Posted bydahamalian2000

RonL

Results 1 to 6 of 6

- Feb 4th 2006, 12:23 PM #1

- Joined
- Feb 2006
- Posts
- 2

## please help!

hi, I am having trouble proving or disproving these two:

First:

If*p*is a prime number, must 2^p - 1 also be prime? Prove or give a counterexample.

Second:

If*n*is a nonnegative integer, must 2^(2^n) + 1 be prime? Prove of give a couterexample.

Thank you so much.

- Feb 4th 2006, 12:29 PM #2

- Joined
- Nov 2005
- From
- someplace
- Posts
- 14,972
- Thanks
- 5

- Feb 4th 2006, 12:34 PM #3

- Joined
- Nov 2005
- From
- someplace
- Posts
- 14,972
- Thanks
- 5

- Feb 4th 2006, 01:05 PM #4

- Joined
- Feb 2006
- Posts
- 2

- Feb 4th 2006, 01:32 PM #5

- Joined
- Nov 2005
- From
- someplace
- Posts
- 14,972
- Thanks
- 5

- Feb 4th 2006, 02:37 PM #6

- Joined
- Nov 2005
- From
- New York City
- Posts
- 10,616
- Thanks
- 10