3 pieces of 4 squares each for 7x7 board
Source: XIV May Olympiad (Olimpiada de Mayo) 2008 L2 P5
September 19, 2022
combinatorics
Problem Statement
Matthias covered a square board, divided into squares, with pieces of the following three types without gaps or overlaps, and without going off the board.
https://cdn.artofproblemsolving.com/attachments/9/9/8a2e63f723cbdf188f22344054f364f1924d47.gif
Each type piece covers exactly squares and each type or type piece covers exactly squares.
Determine the number of pieces of type that Matías could have used.
(Pieces can be rotated and flipped.)