YES 2 decompositions #0 ----------- 5: *(1(),0()) -> 0() 6: *(1(),s(y)) -> s(*(1(),y)) #1 ----------- 1: +(x,0()) -> x 2: +(x,s(y)) -> s(+(x,y)) 3: +(0(),y) -> y 4: +(s(x),y) -> s(+(x,y)) 7: +(x,y) -> +(y,x) 8: +(+(x,y),z) -> +(x,+(y,z)) @Mutually Orthogonal --- R 5: *(1(),0()) -> 0() 6: *(1(),s(y)) -> s(*(1(),y)) --- S 5: *(1(),0()) -> 0() 6: *(1(),s(y)) -> s(*(1(),y)) @Jouannaud and Kirchner's criterion --- R 1: +(x,0()) -> x 2: +(x,s(y)) -> s(+(x,y)) 3: +(0(),y) -> y 4: +(s(x),y) -> s(+(x,y)) 7: +(x,y) -> +(y,x) 8: +(+(x,y),z) -> +(x,+(y,z)) --- S 1: +(x,0()) -> x 2: +(x,s(y)) -> s(+(x,y)) 3: +(0(),y) -> y 4: +(s(x),y) -> s(+(x,y)) 7: +(x,y) -> +(y,x) 8: +(+(x,y),z) -> +(x,+(y,z))