feat(27): cauchy sequences and algebraic characterization
feat(27): cauchy sequences and algebraic characterization

avigad/logic_and_proof,avigad/logic_and_proof,avigad/logic_and_proof,rlewis1988/logic_and_proof,fpvandoorn/logic_and_proof,rlewis1988/logic_and_proof,leanprover/logic_and_proof,leanprover/logic_and_proof,fpvandoorn/logic_and_proof,leanprover/logic_and_proof,rlewis1988/logic_and_proof,fpvandoorn/logic_and_proof