MathDB
IOQM P9 2024

Source:

September 8, 2024

Problem Statement

Consider the grid of points X={(m,n)0m,n4}X = \{(m,n) | 0 \leq m,n \leq 4 \}. We say a pair of points {(a,b),(c,d)}\{(a,b),(c,d)\} in XX is a knight-move pair if (c=a±2( c = a \pm 2 and d=b±1)d = b \pm 1) or (c=a±1( c = a \pm 1 and d=b±2)d = b \pm 2). The number of knight-move pairs in XX is: