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Topic: How to check whether an infinite set is closed under addition?
Replies: 5   Last Post: Jan 15, 2012 9:20 PM

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 Rex Posts: 23 Registered: 10/13/10
How to check whether an infinite set is closed under addition?
Posted: Jan 15, 2012 12:11 AM
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Given k positive numbers a_1<a_2<a_3<...<a_k, and all integers greater
than a_k, we want to check whether this set {a_1, a_2, a_3,...a_k, a_k
+ 1, a_k+2, ......} is closed under addition.

Is there any easy way to do this? any functions that we could use in
Mathematica or Matlab?

Your help will be greatly appreciated.

Date Subject Author
1/15/12 Rex
1/15/12 David Yen
1/15/12 David Yen
1/15/12 David Yen
1/15/12 David Yen
1/15/12 David Yen

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