YES ---- CR(R) ---- Hot decreasingness. R: a(b(c(x))) -> c(c(c(b(b(b(a(a(a(x))))))))) c(b(x)) -> a(a(a(x))) a(x) -> x b(x) -> x c(x) -> x C: c(b(x)) -> a(a(a(x))) a(x) -> x b(x) -> x Label: [a(b(c(x))) -> c(c(c(b(b(b(a(a(a(x)))))))))] = 0 [c(x) -> x] = 0