When a Nested Intersection Empties
Difficulty: Easy · Topics: Discrete Mathematics, Sets
Ichma-ich kesishma bo‘shaganda
For a natural number k, let
A k=\xmid 2k≤ x≤ 22,\ x is a natural number\.
Let m be the smallest k with A 1cap A 2cap A 3cap·scap A k=varnothing. Find n≤ft(A m-4 ).
Natural k son uchun
A k=\xmid 2k≤ x≤ 22,\ x — natural son\
bo‘lsin. A 1cap A 2cap A 3cap·scap A k=varnothing bo‘ladigan eng kichik k ni m deb belgilaymiz. n≤ft(A m-4 ) ni toping.