size 7x7
0 1 1 1 1 1 0
1 1 6 2 2 1 1
1 2 2 1 2 2 1
1 2 3 5 3 2 1
1 2 2 4 2 2 1
1 1 2 4 2 1 1
0 1 1 1 1 1 0