olymmath

EGMO 2012 Problem 4

  • Day 2

A set AA of integers is called sum-full if A⊆A+AA \subseteq A+A, i.e. each element a∈Aa \in A is the sum of some pair of (not necessarily different) elements b,c∈Ab, c \in A. A set AA of integers is said to be zero-sum-free if 0 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?

Origin. Romania (Dan Schwarz). Remark. The original formulation of this problem had a weaker definition of zero-sum-free that did not require all nonzero integers to be sums of finite nonempty subsets of AA.

Dataset text NuminaMath olympiads. Quoted with source.

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

Add a solution

Locator egmo/2012/p4 · Tag 658EZY11DQ · Edit this page on GitHub · Keys: j next, k previous