Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Pairwise Relatively Prime Proof

  1. Jan 30, 2012 #1
    Hi, Can anyone help me how to prove that the two numbers 2^((n-2)/2) -1, 2^(2n) + 1 are relatively prime?
  2. jcsd
  3. Jan 30, 2012 #2
    Hi, Naveenks,
    check the question again; if n is odd, the first number is not an integer.

    Besides, when n=18, the first number would be 2^8-1 = 255, and the second 2^36+1, and both are divisible by 17.
  4. Jan 30, 2012 #3
    Thanks Dodo...I got it that the two numbers are not relatively prime for all values of n...
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook