matrix field=25 rows=14 cols=14
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  1  0  0  0  0  0  0  0  0  0  0  0  0  0
  0  0  0  4  0  0  0  0  0  0  0  0  0  0
  0  0  1  0  0  0  0  0  0  0  0  0  0  0
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  0  0  0  0  0  0  0  0  4  0  0  0  0  0
  0  0  0  0  1  0  0  0  0  0  0  0  0  0
  0  0  0  0  0  0  0  0  0  0  0  4  0  0
  0  0  0  0  0  1  0  0  0  0  0  0  0  0
  0  0  0  0  0  0  0  0  0  0  0  0  0  4
 13 23 21 13  6  2 13  6  6 12 19 15 21 10
  0  0  0  0  0  0  0  1  0  0  0  0  0  0
  2  0 13  9  7 12 12 13 10  7 23 10 11  7
  0  0  0  0  0  0  0  0  0  1  0  0  0  0