Discrete Structures Question
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Raknarg

Posted: Thu Feb 20, 2014 6:30 pm Post subject: Discrete Structures Question 


I have an assignment for this class, and I've answered all the questions but one. The question asks us to prove that for all n >= 1, n(n+1)(n+2) is divisible by 6. I think I might have the idea, where in the range of n to n+2 you will always have a number divisible by 3 and divisible by 2 so they can always be factored out and turned into 6, then removed. However I'm not sure how to prove that. Can anyone help? 





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Tony

Posted: Thu Feb 20, 2014 6:37 pm Post subject: RE:Discrete Structures Question 


By induction.
Assume that factors 2 and 3 exist for N. Given that, show that factors 2 and 3 exist for N+1
N(N+1)(N+2) (case n)
(N+1)(N+2)(N+3) (case n+1)
+1,+2 are common. You need to show that dropping N doesn't matter, or the factor is regained with N+3 
Tony's programming blog. DWITE  a programming contest. 





