1.5 arithmetic operation on a closed cross-
2. reflexive, anti-reflexive, and the symmetry of the closing operation
3. Anti-reflexive, symmetrical, the difference calculation closed antisymmetric
1.5 arithmetic operation on a closed cross-
2. reflexive, anti-reflexive, and the symmetry of the closing operation
3. Anti-reflexive, symmetrical, the difference calculation closed antisymmetric