YES Problem: b(b(d(d(b(b(x1)))))) -> c(c(d(d(b(b(x1)))))) b(b(a(a(c(c(x1)))))) -> b(b(c(c(x1)))) a(a(d(d(x1)))) -> d(d(c(c(x1)))) b(b(b(b(b(b(x1)))))) -> a(a(b(b(c(c(x1)))))) d(d(c(c(x1)))) -> b(b(d(d(x1)))) d(d(c(c(x1)))) -> d(d(b(b(d(d(x1)))))) d(d(a(a(c(c(x1)))))) -> b(b(b(b(x1)))) Proof: Matrix Interpretation Processor: dim=1 interpretation: [d](x0) = x0, [a](x0) = x0 + 1, [b](x0) = x0 + 1, [c](x0) = x0 + 1 orientation: b(b(d(d(b(b(x1)))))) = x1 + 4 >= x1 + 4 = c(c(d(d(b(b(x1)))))) b(b(a(a(c(c(x1)))))) = x1 + 6 >= x1 + 4 = b(b(c(c(x1)))) a(a(d(d(x1)))) = x1 + 2 >= x1 + 2 = d(d(c(c(x1)))) b(b(b(b(b(b(x1)))))) = x1 + 6 >= x1 + 6 = a(a(b(b(c(c(x1)))))) d(d(c(c(x1)))) = x1 + 2 >= x1 + 2 = b(b(d(d(x1)))) d(d(c(c(x1)))) = x1 + 2 >= x1 + 2 = d(d(b(b(d(d(x1)))))) d(d(a(a(c(c(x1)))))) = x1 + 4 >= x1 + 4 = b(b(b(b(x1)))) problem: b(b(d(d(b(b(x1)))))) -> c(c(d(d(b(b(x1)))))) a(a(d(d(x1)))) -> d(d(c(c(x1)))) b(b(b(b(b(b(x1)))))) -> a(a(b(b(c(c(x1)))))) d(d(c(c(x1)))) -> b(b(d(d(x1)))) d(d(c(c(x1)))) -> d(d(b(b(d(d(x1)))))) d(d(a(a(c(c(x1)))))) -> b(b(b(b(x1)))) Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [0] [d](x0) = [0 0 0]x0 + [1] [0 0 0] [0], [1 1 0] [a](x0) = [0 0 1]x0 [0 1 0] , [1 0 0] [b](x0) = [0 0 0]x0 [0 0 0] , [1 0 0] [c](x0) = [0 0 0]x0 [0 0 0] orientation: [1 0 0] [1 0 0] b(b(d(d(b(b(x1)))))) = [0 0 0]x1 >= [0 0 0]x1 = c(c(d(d(b(b(x1)))))) [0 0 0] [0 0 0] [1 0 0] [1] [1 0 0] [0] a(a(d(d(x1)))) = [0 0 0]x1 + [1] >= [0 0 0]x1 + [1] = d(d(c(c(x1)))) [0 0 0] [0] [0 0 0] [0] [1 0 0] [1 0 0] b(b(b(b(b(b(x1)))))) = [0 0 0]x1 >= [0 0 0]x1 = a(a(b(b(c(c(x1)))))) [0 0 0] [0 0 0] [1 0 0] [0] [1 0 0] d(d(c(c(x1)))) = [0 0 0]x1 + [1] >= [0 0 0]x1 = b(b(d(d(x1)))) [0 0 0] [0] [0 0 0] [1 0 0] [0] [1 0 0] [0] d(d(c(c(x1)))) = [0 0 0]x1 + [1] >= [0 0 0]x1 + [1] = d(d(b(b(d(d(x1)))))) [0 0 0] [0] [0 0 0] [0] [1 0 0] [0] [1 0 0] d(d(a(a(c(c(x1)))))) = [0 0 0]x1 + [1] >= [0 0 0]x1 = b(b(b(b(x1)))) [0 0 0] [0] [0 0 0] problem: b(b(d(d(b(b(x1)))))) -> c(c(d(d(b(b(x1)))))) b(b(b(b(b(b(x1)))))) -> a(a(b(b(c(c(x1)))))) d(d(c(c(x1)))) -> b(b(d(d(x1)))) d(d(c(c(x1)))) -> d(d(b(b(d(d(x1)))))) d(d(a(a(c(c(x1)))))) -> b(b(b(b(x1)))) String Reversal Processor: b(b(d(d(b(b(x1)))))) -> b(b(d(d(c(c(x1)))))) b(b(b(b(b(b(x1)))))) -> c(c(b(b(a(a(x1)))))) c(c(d(d(x1)))) -> d(d(b(b(x1)))) c(c(d(d(x1)))) -> d(d(b(b(d(d(x1)))))) c(c(a(a(d(d(x1)))))) -> b(b(b(b(x1)))) Bounds Processor: bound: 1 enrichment: match automaton: final states: {24,18,14,8,1} transitions: b0(7) -> 1* b0(16) -> 25* b0(25) -> 24* b0(11) -> 12* b0(21) -> 22* b0(2) -> 15* b0(20) -> 21* b0(6) -> 7* b0(15) -> 16* b0(10) -> 11* c0(13) -> 8* c0(12) -> 13* c0(3) -> 4* c0(2) -> 3* d0(17) -> 14* d0(4) -> 5* d0(2) -> 19* d0(16) -> 17* d0(23) -> 18* d0(5) -> 6* d0(22) -> 23* d0(19) -> 20* c1(27) -> 28* c1(26) -> 27* f40() -> 2* a0(2) -> 9* a0(9) -> 10* d1(29) -> 30* d1(28) -> 29* b1(30) -> 31* b1(31) -> 32* 24 -> 3,4 14 -> 3,4 16 -> 26* 8 -> 15,16,25,24 1 -> 15,16,22 18 -> 3,4 32 -> 1,16,22,15 problem: Qed