]
qed.
+theorem eq_log_exp: \forall p,n.S O < p \to
+log p (exp p n)=n.
+intros.
+rewrite > times_n_SO in ⊢ (? ? (? ? %) ?).
+rewrite > log_exp
+ [rewrite > log_SO
+ [rewrite < plus_n_O.reflexivity
+ |assumption
+ ]
+ |assumption
+ |apply le_n
+ ]
+qed.
+
+theorem log_exp1: \forall p,n,m.S O < p \to
+log p (exp n m) \le m*S(log p n).
+intros.elim m
+ [simplify in ⊢ (? (? ? %) ?).
+ rewrite > log_SO
+ [apply le_O_n
+ |assumption
+ ]
+ |simplify.
+ apply (trans_le ? (S (log p n+log p (n\sup n1))))
+ [apply log_times.assumption
+ |apply le_S_S.
+ apply le_plus_r.
+ assumption
+ ]
+ ]
+qed.
+
theorem le_log: \forall p,n,m. S O < p \to O < n \to n \le m \to
log p n \le log p m.
intros.