////////////////////////////////////////////////////////////////
//
//     http://www.planetquantum.com/Solve/Level1/Den13/Page55.txt
//
////////////////////////////////////////////////////////////////

Generator:
(C (Csc 1) (^ 7 1/3) 6 7 2)

Problem:
(= (cdot #[[11 88 39 51 5 77 81]
           [21 21 62 61 59 94 52]
           [37 45 51 0 35 27 82]
           [98 34 9 79 62 62 52]
           [65 25 36 66 35 91 84]
           [36 73 57 19 4 87 91]]
         #[[x_1] [x_2] [x_3] [x_4] [x_5] [x_6] [x_7]])
   #[[19] [12] [93] [11] [82] [77]])

Solution:
(= #[[x_1] [x_2] [x_3] [x_4] [x_5] [x_6] [x_7]]
   #[[-74527391]
     [10559202]
     [-214296327]
     [-131242598]
     [138680347]
     [119063754]
     [62718642]])