124720domain: NAppears in sequencesNumber of ways to place 3 nonattacking zebras on a 3 X n board.at n=30A172221Number of ways to pay n dollars using Canadian coins, that is: nickels (5 cents), dimes (10 cents), quarters (25 cents), loonies (100 cents or $1 coins) and toonies ($2 coins).at n=18A307849