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Does there exist a sum-full zero-sum-free set?

Source: 2012 European Girls’ Mathematical Olympiad P4

April 13, 2012
algorithminductionabsolute valuecombinatoricsEGMOEGMO 2012

Problem Statement

A set AA of integers is called sum-full if AA+AA \subseteq A + A, i.e. each element aAa \in A is the sum of some pair of (not necessarily different) elements b,cAb,c \in A. A set AA of integers is said to be zero-sum-free if 00 is the only integer that cannot be expressed as the sum of the elements of a finite nonempty subset of AA. Does there exist a sum-full zero-sum-free set of integers?
Romania (Dan Schwarz)