degree:21
 order:54
[ 21, 4, 28 ][ 21, 12, 0, 0 ]

minimal polynomial:[ x-21, x-3, x, x+15 ][ x-4, x+1 ]
[ x-28, x-10, x, x+8 ]

 SITA:
[ [ [ 1, 0, 0, 0 ], [ 0, 1, 0, 0 ], [ 0, 0, 1, 0 ], [ 0, 0, 0, 1 ] ], 
  [ [ 0, 21, 0, 0 ], [ 1, 0, 4, 16 ], [ 0, 21, 0, 0 ], [ 0, 12, 0, 9 ] ], 
  [ [ 0, 0, 4, 0 ], [ 0, 4, 0, 0 ], [ 1, 0, 3, 0 ], [ 0, 0, 0, 4 ] ], 
  [ [ 0, 0, 0, 28 ], [ 0, 16, 0, 12 ], [ 0, 0, 0, 28 ], [ 1, 9, 4, 14 ] ] ]