# number theory question

• Mar 21st 2009, 12:11 AM
luoginator
number theory question
show that any integer that is greater than 6 is the sum of two relatively prime integers each of which is greater than 1. Actually, how does Bertrand's postulate apply to this question.

cheers
• Mar 21st 2009, 12:55 AM
Opalg
Quote:

Originally Posted by luoginator
show that any integer that is greater than 6 is the sum of two relatively prime integers each of which is greater than 1. Actually, how does Bertrand's postulate apply to this question.

Bertrand's postulate tells you that there is a prime p with $\lceil n/2\rceil< p < 2\lceil n/2\rceil-2\leqslant n-1$. Then p and n–p are coprime.
• Mar 21st 2009, 05:09 AM
luoginator
shot man! cheers..lol