X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Flibrary%2Fnat%2Ffactorial2.ma;h=bb6c72aebccd7092070199095efb69ea6b279fb3;hb=1ee5193677b8e2a80d4f068ee79ecac335de1196;hp=6215d6657892ab39eb0233763885657f35796725;hpb=3f5a0152427fd9a89e7239befd259d27b97aaef5;p=helm.git diff --git a/helm/software/matita/library/nat/factorial2.ma b/helm/software/matita/library/nat/factorial2.ma index 6215d6657..bb6c72aeb 100644 --- a/helm/software/matita/library/nat/factorial2.ma +++ b/helm/software/matita/library/nat/factorial2.ma @@ -12,8 +12,6 @@ (* *) (**************************************************************************) -set "baseuri" "cic:/matita/nat/factorial2". - include "nat/exp.ma". include "nat/factorial.ma". @@ -100,7 +98,7 @@ intro.elim n qed. theorem fact2: \forall n.O < n \to -(exp (S(S O)) ((S(S O))*n))*(fact n)*(fact n) < fact (S((S(S O))*n)). +(exp 2 (2*n))*(fact n)*(fact n) < fact (S(2*n)). intros.elim H [simplify.apply le_S.apply le_n |rewrite > times_SSO. @@ -155,7 +153,7 @@ qed. (* a slightly better result *) theorem fact3: \forall n.O < n \to -(exp (S(S O)) ((S(S O))*n))*(exp (fact n) (S(S O))) \le (S(S O))*n*fact ((S(S O))*n). +(exp 2 (2*n))*(exp (fact n) 2) \le 2*n*fact (2*n). intros. elim H [simplify.apply le_n