1 or 2 is written in a 4X4 grid
Source: ItaMO 2005, P3
March 9, 2012
combinatorics proposedcombinatorics
Problem Statement
In each cell of a table a digit or is written. Suppose that the sum of the digits in each of the four sub-tables is divisible by , but the sum of the digits in the entire table is not divisible by . Find the greatest and the smallest possible value of the sum of the digits.