f(x)=2x in (Z_7,+) is a strong complete mapping of Z_7 since f(0)=0 and both f(x)-x (=x) and f(x)+x (=3x) are permutations of Z_7.
Example of cyclic diagonal Latin square of order 13:
.
0 1 2 3 4 5 6 7 8 9 10 11 12
2 3 4 5 6 7 8 9 10 11 12 0 1 (d=2)
4 5 6 7 8 9 10 11 12 0 1 2 3 (d=4)
6 7 8 9 10 11 12 0 1 2 3 4 5 (d=6)
8 9 10 11 12 0 1 2 3 4 5 6 7 (d=8)
10 11 12 0 1 2 3 4 5 6 7 8 9 (d=10)
12 0 1 2 3 4 5 6 7 8 9 10 11 (d=12)
1 2 3 4 5 6 7 8 9 10 11 12 0 (d=1)
3 4 5 6 7 8 9 10 11 12 0 1 2 (d=3)
5 6 7 8 9 10 11 12 0 1 2 3 4 (d=5)
7 8 9 10 11 12 0 1 2 3 4 5 6 (d=7)
9 10 11 12 0 1 2 3 4 5 6 7 8 (d=9)
11 12 0 1 2 3 4 5 6 7 8 9 10 (d=11)
.
Example of horizontally semicyclic diagonal Latin square of order 13:
.
0 1 2 3 4 5 6 7 8 9 10 11 12
2 3 4 5 6 7 8 9 10 11 12 0 1 (d=2)
4 5 6 7 8 9 10 11 12 0 1 2 3 (d=4)
9 10 11 12 0 1 2 3 4 5 6 7 8 (d=9)
7 8 9 10 11 12 0 1 2 3 4 5 6 (d=7)
12 0 1 2 3 4 5 6 7 8 9 10 11 (d=12)
3 4 5 6 7 8 9 10 11 12 0 1 2 (d=3)
11 12 0 1 2 3 4 5 6 7 8 9 10 (d=11)
6 7 8 9 10 11 12 0 1 2 3 4 5 (d=6)
1 2 3 4 5 6 7 8 9 10 11 12 0 (d=1)
5 6 7 8 9 10 11 12 0 1 2 3 4 (d=5)
10 11 12 0 1 2 3 4 5 6 7 8 9 (d=10)
8 9 10 11 12 0 1 2 3 4 5 6 7 (d=8)
(End)
Example of N-queens problem on toroidal board, N=2*2+1=5, a(2)=2, given by knight with (+1,+2) and (+1,+3) movement parameters starting from top left corner:
.
+-----------+ +-----------+
| Q . . . . | | Q . . . . |
| . . Q . . | | . . . Q . |
| . . . . Q | | . Q . . . |
| . Q . . . | | . . . . Q |
| . . . Q . | | . . Q . . |
+-----------+ +-----------+
.
Example of N-queens problem on toroidal board, N=2*3+1=7, a(3)=4, given by knight with (+1,+2), (+1,+3), (+1,+4), (+1,+5) movement parameters starting from top left corner:
.
+---------------+ +---------------+ +---------------+ +---------------+
| Q . . . . . . | | Q . . . . . . | | Q . . . . . . | | Q . . . . . . |
| . . Q . . . . | | . . . Q . . . | | . . . . Q . . | | . . . . . Q . |
| . . . . Q . . | | . . . . . . Q | | . Q . . . . . | | . . . Q . . . |
| . . . . . . Q | | . . Q . . . . | | . . . . . Q . | | . Q . . . . . |
| . Q . . . . . | | . . . . . Q . | | . . Q . . . . | | . . . . . . Q |
| . . . Q . . . | | . Q . . . . . | | . . . . . . Q | | . . . . Q . . |
| . . . . . Q . | | . . . . Q . . | | . . . Q . . . | | . . Q . . . . |
+---------------+ +---------------+ +---------------+ +---------------+
(End)
|