>>621の前段
(** 1<(1+1/3x_0)…(1+1/3x_s-1)=2^t/3^s -> 3^s<2^t *)
Theorem t1:
forall (x_0 x_s multi s t :nat),
x_0=x_s -> x_s<>0 -> 3^s<>0 ->
3^s*multi > 1 ->
multi > 1 ->
2^t * x_s = x_0 * (3^s * multi) -> 2^t/3^s > 1.
Proof.
intros.
rewrite H in H4.
apply Nat.div_unique_exact in H4.
rewrite Nat.div_mul in H4.
assert(forall (a b:nat), a=b -> b=a).
intros.
omega.
apply H5 in H4.
apply Nat.div_unique_exact in H4.
rewrite H4 in H3.
auto.
auto.
auto.
auto.
Qed.