3 square pieces on 9x9
Source: X May Olympiad (Olimpiada de Mayo) 2004 L2 P5
September 19, 2022
combinatoricscombinatorial geometry
Problem Statement
On a board, divided into squares, pieces of the form
Each piece covers exactly squares.
(a) Starting from the empty board, what is the maximum number of pieces that can be placed?
(b) Starting from the board with pieces already placed as shown in the diagram below, what is the maximum number of pieces that can be placed?
https://cdn.artofproblemsolving.com/attachments/d/4/3bd010828accb2d1811d49eb17fa69662ff60d.gif