YES 1 decompositions #0 ----------- 1: f(f(x,y),z) -> f(x,f(y,z)) 2: f(x,y) -> f(y,x) @Strongly Commuting --- R 1: f(f(x,y),z) -> f(x,f(y,z)) 2: f(x,y) -> f(y,x) --- S 1: f(f(x,y),z) -> f(x,f(y,z)) 2: f(x,y) -> f(y,x)