(VAR N X Y Z X1 X2)
(RULES 
from(X) -> cons(X,n__from(n__s(X)))
2ndspos(0,Z) -> rnil
2ndspos(s(N),cons(X,n__cons(Y,Z))) -> rcons(posrecip(activate(Y)),2ndsneg(N,activate(Z)))
2ndsneg(0,Z) -> rnil
2ndsneg(s(N),cons(X,n__cons(Y,Z))) -> rcons(negrecip(activate(Y)),2ndspos(N,activate(Z)))
pi(X) -> 2ndspos(X,from(0))
plus(0,Y) -> Y
plus(s(X),Y) -> s(plus(X,Y))
times(0,Y) -> 0
times(s(X),Y) -> plus(Y,times(X,Y))
square(X) -> times(X,X)
from(X) -> n__from(X)
s(X) -> n__s(X)
cons(X1,X2) -> n__cons(X1,X2)
activate(n__from(X)) -> from(activate(X))
activate(n__s(X)) -> s(activate(X))
activate(n__cons(X1,X2)) -> cons(activate(X1),X2)
activate(X) -> X
)