Prove Nonempty Subset Sum of 5 Distinct Single-Digit Integers

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The discussion centers on proving that it is impossible to have a set B of 5 distinct positive single-digit integers such that every possible nonempty subset of B has a different sum. The total number of nonempty subsets for 5 distinct integers is 31, derived from 2^5 - 1. However, the maximum possible sum of any 4 distinct single-digit integers is 28, which leads to the application of the pigeonhole principle to demonstrate that at least two subsets must share the same sum.

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No idea where to start with this one...to prove that it is not possible to have a set B of 5 distinct positive single-digit integers such that every possible nonempty subset of B has a different sum. How do I approach it/do it?
 
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Given 5 distinct numbers, there are 2^5 - 1 possible sums of subsets, excluding the sum of all 5 which is 31.

However, the biggest possible sum of 4 distinct single digit numbres is 9+8+7+6= 28, so apply the pigeon hole principle.
 
I'll try that, thanks for the suggestion!
 

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