8.2

Part of 2001 All-Russian Olympiad Regional Round

Problems(1)

n numbers 1s and 2s in a circle - All-Russian MO 2001 Regional (R4) 8.2

Source:

N

numbers - ones and twos - are arranged in a circle. We mean a number formed by several digits arranged in a row (clockwise or counterclockwise). For what is the smallest value of

N

, all four-digit numbers whose writing contains only numbers

1

2

, could they be among those shown?

algebranumber theory