MathDB

1

Part of 2011 Philippine MO

Problems(1)

Finite Set Property

Source: 2011 Philippine Math Olympiad National Stage Problem 1

7/15/2013
Find all nonempty finite sets XX of real numbers such that for all x∈Xx\in X, x+∣x∣∈Xx+|x| \in X.
combinatorics unsolvedcombinatoricsSets