"Book 13 covers the Sequences topic found in highschool courses. \n\nIt shows how mathematical skills developed in the earlier books can be applied in a new practical context.\n\nThe book's use of plain language enables students to develop deeper understanding. It also makes it useful for parents assisting their children as they progress through school. \n\nContaining material that has been used in classrooms, the electronic format makes it easy to use when teachers are seeking additional teaching resources."