YES Problem: not(x) -> if(x,false(),true()) and(x,y) -> if(x,y,false()) or(x,y) -> if(x,true(),y) implies(x,y) -> if(x,y,true()) =(x,x) -> true() =(x,y) -> if(x,y,not(y)) if(true(),x,y) -> x if(false(),x,y) -> y if(x,x,if(x,false(),true())) -> true() =(x,y) -> if(x,y,if(y,false(),true())) Proof: Bounds Processor: bound: 2 enrichment: top automaton: final states: {8,7,1} transitions: not1(7) -> 1* not1(1) -> 1* not1(8) -> 1* true2() -> 8*,1,5 if2(7,7,8) -> 1* if2(7,7,5) -> 1* if2(8,6,8) -> 1* if2(8,6,5) -> 1* if2(1,7,8) -> 1* if2(1,7,5) -> 1* if2(7,6,8) -> 1* if2(7,6,5) -> 1* if2(8,7,8) -> 1* if2(8,7,5) -> 1* if2(1,6,8) -> 1* if2(1,6,5) -> 1* false2() -> 7*,1,6 and0(8,1) -> 1* and0(8,7) -> 1* and0(1,8) -> 1* and0(7,1) -> 1* and0(7,7) -> 1* and0(8,8) -> 1* and0(1,1) -> 1* and0(1,7) -> 1* and0(7,8) -> 1* or0(8,1) -> 1* or0(8,7) -> 1* or0(1,8) -> 1* or0(7,1) -> 1* or0(7,7) -> 1* or0(8,8) -> 1* or0(1,1) -> 1* or0(1,7) -> 1* or0(7,8) -> 1* implies0(8,1) -> 1* implies0(8,7) -> 1* implies0(1,8) -> 1* implies0(7,1) -> 1* implies0(7,7) -> 1* implies0(8,8) -> 1* implies0(1,1) -> 1* implies0(1,7) -> 1* implies0(7,8) -> 1* =0(8,1) -> 1* =0(8,7) -> 1* =0(1,8) -> 1* =0(7,1) -> 1* =0(7,7) -> 1* =0(8,8) -> 1* =0(1,1) -> 1* =0(1,7) -> 1* =0(7,8) -> 1* if1(1,7,7) -> 1* if1(1,1,1) -> 1* if1(8,8,8) -> 1* if1(7,8,7) -> 1* if1(1,7,1) -> 1* if1(8,1,7) -> 1* if1(8,7,7) -> 1* if1(7,8,1) -> 1* if1(8,1,1) -> 1* if1(8,7,1) -> 1* if1(1,1,8) -> 1* if1(1,7,8) -> 1* if1(7,8,8) -> 1* if1(1,8,7) -> 1* if1(8,1,8) -> 1* if1(7,1,7) -> 1* if1(8,7,8) -> 1* if1(7,7,7) -> 1* if1(1,8,1) -> 1* if1(7,1,1) -> 1* if1(7,7,1) -> 1* if1(8,8,7) -> 1* if1(8,8,1) -> 1* if1(1,8,8) -> 1* if1(7,1,8) -> 1* if1(7,7,8) -> 1* if1(1,1,7) -> 1* 5 -> 1* 6 -> 1* 7 -> 1* 8 -> 1* problem: Qed