∀ n, O = (O - n)

Theorem minus_O_n : forall (n:nat), logic.eq (nat) O (minus O n).

theorem minus_O_n : \forall (n:nat). (eq) (nat) (O) ((minus) (O) n).

theorem minus_O_n : forall (n:nat.nat) , (((logic.eq_) (nat.nat)) ((nat.O) )) ((((nat.minus) ) ((nat.O) )) (n)).

minus_O_n : LEMMA (FORALL(n:nat_sttfa.sttfa_nat):logic_sttfa_th.eq[nat_sttfa.sttfa_nat](nat_sttfa.sttfa_O)(nat_sttfa.minus(nat_sttfa.sttfa_O)(n)))

Printing for OpenTheory is not working at the moment.