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Consecutive Primes (Posted on 2005-01-24) Difficulty: 2 of 5
Show that the sum of two consecutive odd primes has at least 3 (not necessarily distinct) prime factors. For example,

3+5=2*2*2
5+7=2*2*3
7+11=2*3*3

See The Solution Submitted by David Shin    
Rating: 3.1667 (6 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution at least 3 | Comment 2 of 6 |
1 is not a prime number

let 1st odd prime be 2*n-1
then the 2nd 2*n+1


the sum is 4*n=2*2*n

q.e.d.
  Posted by Ady TZIDON on 2005-01-24 15:14:59
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