124

Part of 1947 Moscow Mathematical Olympiad

Problems(1)

MMO 124 Moscow MO 1947 one relative prime in 4 of 5 consecutive

Source:

a) Prove that of

5

consecutive positive integers one that is relatively prime with the other

4

can always be selected.
b) Prove that of

10

consecutive positive integers one that is relatively prime with the other

9

can always be selected.

number theoryrelatively primeconsecutivecombinatorics