Question
Oliver is a frequent visitor to More!, his favorite restaurant. Since it's introduction, Oliver has ordered the special offer More! For Less' menu every time.
Starter
Melon Balls
Salmon Mousse
Egg Mayonaisse
Main Course
Chicken and Mushroom Pie
Lasagne
Tuna Bake
Cheese and Onion Pie
Desert
Apple Pie
Chocolate Mouse
Ice Cream
He has now ordered from this menu 11 times without ever repeating his combination of choices for the 3 courses.
Note that 'mousse' and 'pie' appear more than once on this menu. In the same meal he doesn't want to choose pie twice or mousse twice.
How many more times can Oliver order from the 'More! For Less' menu before he must have a combination he has already eaten?