A:= [[ 2, 4, 3,-1,-5], 
     [ 3,-5,-2, 4, 1], 
     [ 2, 3, 4, 5, 1], 
     [ 1, 5, 2,-4, 3], 
     [-5, 1, 3, 4, 2], 
     [-4, 5, 2,-1, 3]]: