Over 2000 numbers are around a circle. Each number is the sum of its left and right neighbors.

Given that one of the numbers is a one, how many numbers (as a minimum) must there be?

(In reply to quick answer by armando)

I  agree with Armando.

If one of the numbers is 1, these are the terms that closes a loop :

(-a), (1-a), (1), (a), (a-1), (-1), (-a).

So the six terms will be repeated, and the first multiple of 6 over 2,000 is 2,004. 

Posted by pcbouhid on 2005-05-27 16:24:05