YES(?,O(n^3)) Problem: a(b(a(x1))) -> a(b(b(a(x1)))) b(b(b(x1))) -> b(b(x1)) Proof: RT Transformation Processor: strict: a(b(a(x1))) -> a(b(b(a(x1)))) b(b(b(x1))) -> b(b(x1)) weak: Bounds Processor: bound: 1 enrichment: match-rt automaton: final states: {3} transitions: a1(12) -> 13* a1(9) -> 10* b1(25) -> 26* b1(10) -> 11* b1(11) -> 12* a0(3) -> 3* b0(3) -> 3* 3 -> 9* 13 -> 10,25,3 26 -> 11* problem: strict: b(b(b(x1))) -> b(b(x1)) weak: a(b(a(x1))) -> a(b(b(a(x1)))) Matrix Interpretation Processor: dimension: 3 interpretation: [1 0 2] [1] [b](x0) = [0 0 1]x0 + [0] [0 0 0] [0], [1 2 0] [3] [a](x0) = [0 0 0]x0 + [1] [0 0 0] [2] orientation: [1 0 2] [3] [1 0 2] [2] b(b(b(x1))) = [0 0 0]x1 + [0] >= [0 0 0]x1 + [0] = b(b(x1)) [0 0 0] [0] [0 0 0] [0] [1 2 0] [15] [1 2 0] [12] a(b(a(x1))) = [0 0 0]x1 + [1 ] >= [0 0 0]x1 + [1 ] = a(b(b(a(x1)))) [0 0 0] [2 ] [0 0 0] [2 ] problem: strict: weak: b(b(b(x1))) -> b(b(x1)) a(b(a(x1))) -> a(b(b(a(x1)))) Qed