////////////////////////////////////////////////////////////////
//
//     http://www.planetquantum.com/Solve/Level1/Den13/Page10.txt
//
////////////////////////////////////////////////////////////////

Generator:
(C (^ _E 2) (Cot 1) 6 7 3)

Problem:
(= (cdot #[[738 905 609 893 65 22 723]
           [42 746 57 500 781 318 31]
           [557 55 184 732 408 712 782]
           [252 257 379 607 905 776 338]
           [431 248 507 912 179 477 375]
           [316 126 547 886 612 388 460]]
         #[[x_1] [x_2] [x_3] [x_4] [x_5] [x_6] [x_7]])
   #[[642] [92] [615] [934] [330] [703]])

Solution:
(= #[[x_1] [x_2] [x_3] [x_4] [x_5] [x_6] [x_7]]
   #[[-38940233591421633]
     [9013441181980168]
     [8157511396494645]
     [-861150647629766]
     [-11283210244514215]
     [9321359196583813]
     [23388865798359386]])