{{1, 0, 0, -2, 0, 0, 0, 0, -2, 0, 3, -1/2, 0, 1/2, 1, 0, 1/2, -2}, 
 {0, 1, 0, 0, 2, 1, 0, 1, 0, 1, -5, 0, -1/2, 1/2, 0, -1, 0, 2}, 
 {0, 0, 1, 0, 0, 0, 0, 0, 0, 0, -3, 0, 0, 0, 0, 0, 0, 1}, 
 {0, 0, 0, 0, 0, 0, 1, 0, -1, -1, 3, 0, 0, -1/2, 0, 0, 0, -1}}
