YES(?,O(n^1))

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

Proof:
 Bounds Processor:
  bound: 1
  enrichment: match
  automaton:
   final states: {4,3,2}
   transitions:
    a1(22) -> 23*
    a1(12) -> 13*
    a1(14) -> 15*
    a1(8) -> 9*
    b1(21) -> 22*
    b1(11) -> 12*
    b1(13) -> 14*
    s1(9) -> 10*
    a0(1) -> 2*
    s0(1) -> 1*
    b0(1) -> 3*
    c0(1) -> 4*
    1 -> 11,8
    10 -> 21,9,2
    15 -> 4*
    23 -> 14*
  problem:
   
  Qed