MathDB
Paritioning positive integers into A and B with conditions

Source: Baltic Way 1996 Q20

February 22, 2005
arithmetic sequencecombinatorics unsolvedcombinatorics

Problem Statement

Is it possible to partition all positive integers into disjoint sets AA and BB such that (i) no three numbers of AA form an arithmetic progression, (ii) no infinite non-constant arithmetic progression can be formed by numbers of BB?