While there are 192 mazes on a 3 X 3 grid, only a(3) = 28 are distinct mod rotations and reflections.
21 are asymmetric:
_____ _____ _____ _____ _____ _____ _____ _____
| | | | | | | _| | _| | _| | _| | _|
| | |_| | |_| | | |_|_| | | | | | _| | |_ | | |_ | | |_ _|
|_|_ _| |_ _|_| |_ _ _| |_|_|_| |_|_ _| |_ _|_| |_|_ _| |_ _ _|
_____ _____ _____ _____ _____ _____ _____ _____
| _| | _| | _| | _| | _| | _ | | _ | | _ |
|_| | |_| _| |_|_ | | | | | | |_| | |_ | | |_ |_| |_ _| |
|_ _|_| |_ _ _| |_ _ _| |_|_ _| |_ _ _| |_ _|_| |_ _ _| |_ _ _|
_____ _____ _____ _____ _____
| _ _| | _ _| |_ _| |_ _| |_ _|
|_ | |_ _| | _| | _ | | | |
|_ _|_| |_ _ _| |_|_ _| |_ _|_| |_|_ _|
.
5 have 2-way symmetry:
_____ _____ _____ _____ _____
| | | | | _| | _ _| |_ _|
| | | | |_| |_| |_| | | |_ _ | | |
|_|_|_| |_ _ _| |_ _ _| |_ _ _| |_|_|_|
.
2 have 4-way symmetry:
_____ _____
|_ _| |_ | |
|_ _| | _|
|_ _ _| |_|_ _|
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