MathDB
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 4×44 \times 4 table a digit 11 or 22 is written. Suppose that the sum of the digits in each of the four 3×33 \times 3 sub-tables is divisible by 44, but the sum of the digits in the entire table is not divisible by 44. Find the greatest and the smallest possible value of the sum of the 1616 digits.