{{1, 0, 0, 0, 1, -1, 0, 1, 1, -1/2, -2, 0, -1/2}, 
 {0, 1, 0, 0, -1/2, -1/2, 0, 0, -1/2, -1/4, 0, 1/2, -1/4}, 
 {0, 0, 1, 0, -1, -1, 1, 0, -1, 0, 0, 1, -1}, {0, 0, 0, 1, -1/2, -1/2, 1, 0, 
  -1/2, 3/4, 0, 1/2, -1/4}}
