Hi.
I recently stumbled upon this question and still can't figure out how to prove it. This is a GCSE question and it has never been this hard before.
k=2p−1 N=k2−1 Show that 2^(p+1) is a factor of N
k=2p−1
N=k2−1
Show that 2^(p+1) is a factor of N
Thanks in advance,
bqrs01
You say "Show that N is a factor of 2^(p+1)" ??. Are you sure it is not the reverse? That is:
Show that 2^(p+1) is a factor of N?
ok :)
k=2p−1N=k2−1N=(2p−1)2−1N=22p−2∗2p+1−1N=2p∗2p−2∗2pN=2p(2p−2)N=2p+1(2p−1−1)so2p+1 is a factor of N
So I have shown that 2^(p+1) is a factor of N
Which is the other way around from what you asked.
