This problem can be analyzed and found as follows:

1->； 2: 1 species

1->； 3: 1 species

1->； 4:3 kinds

1->； 5: 1 species

1->； 6:5 species

1->； 7: 1 species

1->； 8:7 species

1->； 9: 1 species

1->； 10:9 species

In fact, odd cells must pass through their adjacent odd cells, so there is only one way to reach them.

In order to reach even squares, you need to take this route ... my''''', or ... my route.

After many attempts on the graph, it is found that the way to reach even n is n- 1.