例文
- This is because all 24 possible positions and orientations of the first corner are equivalent because of the lack of fixed centres.
- A tension length can be seen as a fixed centre point, with the two half tension lengths expanding and contracting with temperature.
- This factor does not appear when calculating the permutations of N譔譔 cubes where N is odd, since those puzzles have fixed centres which identify the cube's spatial orientation.