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You are not logged in. #1 20050922 07:23:07
Problem with prime numbersI need to prove that if p is a prime number ending on 1 (like 11, 101), p+4 is a multiple of 15. It is obvious that it's a multiple of 5, so i just have to prove that it's also a multiple of 3. But how? I have really tried, but I just can't work it out. #2 20050922 21:59:30
Re: Problem with prime numbersHaven't worked it out for you yet, but you could try looking for a proof that p+1 is divisible by 3 (because if p+4 is, then p+1 is and vice versa) "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #3 20050928 00:22:39
Re: Problem with prime numbersrespected sir im a guy form india. have question about the prime #4 20051205 07:39:26
Re: Problem with prime numbersSuch a nice request, but noone answered it? It slipped under my radar. "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #5 20051205 07:42:11
Re: Problem with prime numbersSchool is practice for the future. Practice makes perfect. But  nobody's perfect, so why practice? 