MAYBE

Problem:
 a(x1) -> b(x1)
 a(c(x1)) -> c(c(a(b(x1))))
 b(b(x1)) -> a(x1)

Proof:
 RT Transformation Processor:
  strict:
   a(x1) -> b(x1)
   a(c(x1)) -> c(c(a(b(x1))))
   b(b(x1)) -> a(x1)
  weak:
   
  Matrix Interpretation Processor:
   dimension: 1
   interpretation:
    [c](x0) = x0 + 9,
    
    [b](x0) = x0 + 20,
    
    [a](x0) = x0 + 21
   orientation:
    a(x1) = x1 + 21 >= x1 + 20 = b(x1)
    
    a(c(x1)) = x1 + 30 >= x1 + 59 = c(c(a(b(x1))))
    
    b(b(x1)) = x1 + 40 >= x1 + 21 = a(x1)
   problem:
    strict:
     a(c(x1)) -> c(c(a(b(x1))))
    weak:
     a(x1) -> b(x1)
     b(b(x1)) -> a(x1)
   Open