#g2 f1

5x5
0 1 0 0 0
1 0 0 0 0
0 0 1 0 0
0 0 0 1 0
0 0 0 0 1

5x5
-1 0 0 0 0
1 1 1 1 1
0 -1 0 0 0
0 0 -1 0 0
0 0 0 -1 0

5x5
2 1 1 1 1
1 2 1 1 1
1 1 2 1 1
1 1 1 2 1
1 1 1 1 2

2^5*3^2*5 = 1440

dim5/5-2b

