Donald has nine one-day passes to Dizzyworld. He can go alone and use one, or he can take a friend and use two. If he visits every day until he uses all the passes, in how many different ways can he use them? Using a two day for four days and then going alone at the end (2,2,2,2,1) is different from reversing the order (1,2,2,2,2).

I don't know the answer to this question.