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 re(2): Picky, picky! - I think I got it !! - better !!! by pcbouhid)

I don't understand.  "adding two five strings ..." looks like this

(1/2) (-1/2) (-1) (-1/2) (1/2) (1/2) (-1/2) (-1) (-1/2) (1/2)

doesn't it?  But the middle string, (1/2) (1/2) (-1/2), violates the sum of neighbors condition.  What am I missing?

Posted by McWorter on 2005-05-31 03:55:16