# HG changeset patch # User huffman # Date 1313352297 25200 # Node ID 1d2bf1f240ac3cd70b86eab23412c0f868287e34 # Parent ea99698c207042e9f516e18042bed0d29bfd76d4 generalize lemma convergent_subseq_convergent diff -r ea99698c2070 -r 1d2bf1f240ac src/HOL/SEQ.thy --- a/src/HOL/SEQ.thy Sun Aug 14 11:44:12 2011 -0700 +++ b/src/HOL/SEQ.thy Sun Aug 14 13:04:57 2011 -0700 @@ -691,9 +691,13 @@ apply (blast intro: seq_suble le_trans dest!: spec) done +lemma convergent_subseq_convergent: + "\convergent X; subseq f\ \ convergent (X o f)" + unfolding convergent_def by (auto intro: LIMSEQ_subseq_LIMSEQ) + + subsection {* Bounded Monotonic Sequences *} - text{*Bounded Sequence*} lemma BseqD: "Bseq X ==> \K. 0 < K & (\n. norm (X n) \ K)" @@ -1007,11 +1011,6 @@ shows "Cauchy X = convergent X" by (fast intro: Cauchy_convergent convergent_Cauchy) -lemma convergent_subseq_convergent: - fixes X :: "nat \ 'a::complete_space" - shows "\ convergent X; subseq f \ \ convergent (X o f)" - by (simp add: Cauchy_subseq_Cauchy Cauchy_convergent_iff [symmetric]) - text {* Proof that Cauchy sequences converge based on the one from http://pirate.shu.edu/~wachsmut/ira/numseq/proofs/cauconv.html