YES Problem: a(a(b(b(b(b(a(a(x1)))))))) -> a(a(c(c(a(a(b(b(x1)))))))) a(a(c(c(x1)))) -> c(c(c(c(a(a(x1)))))) c(c(c(c(c(c(x1)))))) -> b(b(c(c(b(b(x1)))))) Proof: Matrix Interpretation Processor: dim=4 interpretation: [1 0 0 0] [0 1 0 0] [b](x0) = [0 0 0 0]x0 [0 1 0 0] , [1 0 0 1] [0] [0 0 1 0] [0] [a](x0) = [0 1 1 0]x0 + [1] [0 0 0 0] [0], [1 0 0 0] [0 0 0 0] [c](x0) = [0 0 0 0]x0 [0 0 0 1] orientation: [1 1 1 1] [1] [1 1 0 0] [0] [0 1 1 0] [2] [0 0 0 0] [1] a(a(b(b(b(b(a(a(x1)))))))) = [0 1 1 0]x1 + [3] >= [0 0 0 0]x1 + [2] = a(a(c(c(a(a(b(b(x1)))))))) [0 0 0 0] [0] [0 0 0 0] [0] [1 0 0 1] [0] [1 0 0 1] [0 0 0 0] [1] [0 0 0 0] a(a(c(c(x1)))) = [0 0 0 0]x1 + [2] >= [0 0 0 0]x1 = c(c(c(c(a(a(x1)))))) [0 0 0 0] [0] [0 0 0 0] [1 0 0 0] [1 0 0 0] [0 0 0 0] [0 0 0 0] c(c(c(c(c(c(x1)))))) = [0 0 0 0]x1 >= [0 0 0 0]x1 = b(b(c(c(b(b(x1)))))) [0 0 0 1] [0 0 0 0] problem: a(a(c(c(x1)))) -> c(c(c(c(a(a(x1)))))) c(c(c(c(c(c(x1)))))) -> b(b(c(c(b(b(x1)))))) Bounds Processor: bound: 1 enrichment: match automaton: final states: {8,1} transitions: a0(3) -> 4* a0(2) -> 3* b1(68) -> 69* b1(22) -> 23* b1(33) -> 34* b1(29) -> 30* b1(32) -> 33* b1(53) -> 54* b1(26) -> 27* b1(63) -> 64* b1(21) -> 22* b1(25) -> 26* b1(67) -> 68* b1(64) -> 65* b1(50) -> 51* b1(54) -> 55* b1(49) -> 50* b1(28) -> 29* b0(13) -> 8* b0(12) -> 13* b0(2) -> 9* b0(9) -> 10* c0(11) -> 12* c0(4) -> 5* c0(6) -> 7* c0(10) -> 11* c0(7) -> 1* c0(5) -> 6* f30() -> 2* c1(52) -> 53* c1(66) -> 67* c1(24) -> 25* c1(31) -> 32* c1(51) -> 52* c1(30) -> 31* c1(23) -> 24* c1(65) -> 66* 27 -> 7* 69 -> 5* 7 -> 63* 4 -> 49* 6 -> 28* 1 -> 3,4 55 -> 6* 34 -> 1,4 5 -> 21* problem: Qed