chess knight in $8 \times 8$ board
Source: 45th International Tournament of Towns, Junior A-Level P1, Fall 2023
December 16, 2023
combinatorics
Problem Statement
1. Every square of a board is filled with a positive integer, such that the following condition holds: if a chess knight can move from some square to another then the ratio of numbers from these two squares is a prime number. Is it possible that some square is filled with 5 , and another one with 6 ?Egor Bakaev