(from AG01 4.23)
(VAR x y z)
(RULES
quot(0,s(y),s(z)) -> 0
quot(s(x),s(y),z) -> quot(x,y,z)
plus(0,y) -> y
plus(s(x),y) -> s(plus(x,y))
quot(x,0,s(z)) -> s(quot(x,plus(z,s(0)),s(z)))
)