Wat ?
Here is an example of an improved enumeration of points from 1 to 10. If we take the cost of one inversion as $1, then we save $4: starting from point 3, we make a step of 5 in the cycle, points 1,2,6,7 are formed using the calculated inversion for 4,5,9,10 respectively.
$1 $1
---------+-------------------+---------
$0 | $1 $0 | $1
.-------+-------. .-------+-------.
| $0 | $1 | | $0 | $1 |
| .---+---. | | .---+---. |
| | | | | | | | | |
1 2 3 4 5 6 7 8 9 10