with(linalg):
A := matrix(5,5,[1,1,1,0,0, 
                 1,2,0,1,0,
                 3,2,0,0,1,
                 3,0,2,0,3,
                 0,2,0,0,1]);
inverse(A);
det(A);
                          [1    1    1    0    0]
                          [                     ]
                          [1    2    0    1    0]
                          [                     ]
                     A := [3    2    0    0    1]
                          [                     ]
                          [3    0    2    0    3]
                          [                     ]
                          [0    2    0    0    1]


                 [ 0      0    1/3      0      -1/3]
                 [                                 ]
                 [1/4     0    1/24    -1/8    1/3 ]
                 [                                 ]
                 [3/4     0    -3/8    1/8      0  ]
                 [                                 ]
                 [              -5                 ]
                 [-1/2    0     --     1/4     1/3 ]
                 [              12                 ]


                                 -24