0 1 2 0
 1 2 0 1
 2 0 1 2
=========================
 0 0 0 0
 0 0 0 0
 0 0 0 0
=========================
 0 1 2 0
 1 2 0 1
 2 0 1 2
=========================
 -2 -1 0 -2
 -1 0 -2 -1
 0 -2 -1 0
=========================
 -1 0 1 -1
 0 1 -1 0
 1 -1 0 1
=========================
 1 2 3 0 0
 2 4 6 0 0
 3 6 9 0 0
 4 8 12 0 0
 0 0 0 0 0
 0 0 0 0 0
=========================
 0 0 0
 0 1 2
 0 2 4
 0 3 6
 0 4 8
=========================
 0 0 0 0
 0 1 2 3
 0 2 4 6
=========================
 0 0 0 0 1 2 0 2 4 0 3 6
=========================
 6 2 3
=========================
 -9 -6 -3 0 3
=========================