Nonattacking Queens on a Triangle
Gabriel Nivasch, Eyal Lev · Mathematics Magazine · 2005
Most readers are surely familiar with the problem of placing eight non-attacking queens on a chessboard, and its natural generalization to an n × n board (see the references at the end of this note). Here we consider an interesting variant of this problem, in which the board is triangular. We are given a triangular board of side n. A queen on the board can move along a straight line parallel to any of the board’s sides (see Figure 1). Our problem is to place on the board as many queens as possible, without any two queens attacking each other. Obviously no more than n queens can be placed, since no row can contain more than one queen. ∗ Corresponding author. Figure 1: A queen on a triangular board.