(VAR x1 )
(RULES 
        c(c(x1)) -> a(a(a(b(b(b(x1))))))
        b(b(b(a(x1)))) -> b(b(b(b(b(b(b(b(x1))))))))
        b(b(c(c(x1)))) -> c(c(c(a(a(a(a(x1)))))))
        
)