Problems (p15-18): 1, 3, 5, 7, 9, 12, 13, 19, 25, 28.
Theoretical exercises (p18-22): 2, 8, 9, 10, 13.
Bonus question:
Consider a standard 8 x 8 chess board. A rook is a piece in the game.
Two rooks are said to "attack" each other if they occupy squares on the same
horizontal or vertical line.
(a) In how many ways can 8 rooks be positioned on the board so that no two are
attacking each other?
(b) In how many ways can 7 rooks be positioned on the board so that no two are
attacking each other?
(c) In how many ways can n rooks (n=1,2,...,8)
be positioned on the board so that no two are attacking each other?