Question

prove 2^66-1 is not prime

Answer 1

\[2^{66}-1 = 4^{33}-1 = (4-1)(4^{32}+4^{31}+\cdots +1)\]

Answer 2

i dint even note ! wow !

Answer 3

we have this nice relation :

\(2^a-1\) is a prime \(\iff\) \(a\) is a prime

Answer 4

look up mersenne primes for more cool stuff..

Answer 5

seems like