StevenXClontz’s Twitter Archive—№ 2,665

Spoiler: {0,2,3,4,6} works since every pair is a subset of {0,2,4}, {0,3,6}, {2,3,4}, or {2,4,6}. So more generally we have {0,2x,3x,4x,6x} and {y,y+2x,y+3x,y+4x,y+6x}.