When all three numbers are different, there are combinations of 1 and 120.
2. There are 90 kinds when two numbers are the same.
3. When three numbers are the same, there are 10 kinds.
So there are 220 kinds of * * *.
Extended data
Interesting combination of numbers:
142857, also known as the number of lanterns. It exists in the pyramids of Egypt and is a magical number.
It is proved that there are seven days in a week, and each time it is accumulated by itself, its six numbers will rotate in turn. On the seventh day, they had a holiday, and changed to 99999, and the number was getting bigger and bigger. Each cycle is more than one week, and each number needs to be copied once, without a computer. As long as we know its replication method, we can know the accumulated answers.