Sect 4. Sequences CONCEPTS Sequence Applications: summations, strings, languages Inductive definitions Principle of induction Recurrence NOTATION SKILLS 1. Identify concepts in a context E.g., find limits of a summation E.g., find base case of a recurrence E.g., identify inductive assumption of proof by induction 2. Manipulate summations E.g., prove summation theorem by induction E.g., find close form of a summation 3. Understand language definition E.g., tell whether a string is in a language E.g., find product, union, closure of languages 4. Understand inductive definitions E.g., compute set inductively defined E.g., produce inductive definition of a set 5. Understand induction principle E.g., tell structure of a proof by induction 6. Manipulate recurrences E.g., find close form of a recurrence E.g., express recurrence for a given problem/algorithm READING Wikibooks: Undergraduate Mathematics/Sequence https://en.wikibooks.org/wiki/Undergraduate_Mathematics/Sequence exclude "Limits and convergence" and following sections Wikipedia: Formal language https://en.wikipedia.org/wiki/Formal_language only paragraphs: "Words over an alphabet", "Definition", "Operations on languages" *** Recommended *** Wikibooks: Calculus/Summation notation https://en.wikibooks.org/wiki/Calculus/Summation_notation Wikipedia: Summation (like the wikibook, but a bit heavier) https://en.wikipedia.org/wiki/Summation *** Recommended *** Wikibooks: Mathematical Proof/Methods of Proof/Proof by Induction https://en.wikibooks.org/wiki/Mathematical_Proof/Methods_of_Proof/Proof_by_Induction Youtube: Principle of Mathematical Induction Inequality Proof by The Math Sorcerer https://www.youtube.com/watch?v=g0EFrCYgl5s (a short example) Youtube: Inductive step of proving an inequality by induction by Discrete Math Zyante https://www.youtube.com/watch?v=GkMKPRt5jL0 (a short example) *** Recommended *** Youtube: Finding a closed form from a recursively defined sequence by Joshua Helston (short, clean example) https://www.youtube.com/watch?v=pHL3g3oQhyg *** Recommended *** Lerma, sect 4.1-4.3 (exclude 4.2.3, 4.3.2) Smid, sect 2.2.5 (Induction) 4.3 (Induction definions) 4.5.2 (eample of running time) LLM, Sect 5 (Induction, long, extensive, entertaining) Chapt 21 (Recurrences, long, extensive) ADS, sect 3.7 (Induction) Chap 8 (recursion and recurrences) BDS, Sect 4.1-4.3 (heavy) Hammack, Chap 10 (!!! lots of examples and exercises !!!) Levin, Sect 2.5 (induction) 2.4 (recurrences)