TOT 130 1986 Autumn S6 numbers 1-32 twice in a 8x8 chessboard
Source:
August 29, 2019
combinatoricssquare table
Problem Statement
Squares of an chessboard are each allocated a number between and , with each number being used twice. Prove that it is possible to choose such squares, each allocated a different number, so that there is at least one such square on each row or column . (A . Andjans, Riga