Y by Adventure10
Among the
inhabitants of an island, where
is even, every two are either friends or enemies. Some day, the chief of the island orders that each inhabitant (including himself) makes and wears a necklace consisting of marbles, in such a way that two necklaces have a marble of the same type if and only if their owners are friends.
(a) Show that the chief’s order can be achieved by using
different types of stones.
(b) Prove that this is not necessarily true with less than
types.


(a) Show that the chief’s order can be achieved by using

(b) Prove that this is not necessarily true with less than
