Classes

Class 1: What Makes it Go?

  • What makes computers go?
  • Introduction to Discrete Math (Kevin Bacon)
  • Course Logistics
  • Why discrete math?

Class 2: Truth and Soundness

  • Defense of Analog Computing
  • “Hard” Problems
  • Propositions
  • Booleans
  • Operations on Booleans

Class 3: Inference

  • Defining Boolean (Continued)
  • Revisiting Propositions
  • Implies (Logical operator)
  • Axioms, Inference Rules, Predicates
  • Soundness
  • Contrapositive

Class 4: Proof

  • Recap: Inference Rules and Soundness
  • Contrapositive
  • Introduction to Proof (Odd Square Theorem, Even Square Theorem)

Class 5: Proof by Contradiction

  • Recap: Proof by Contrapositive
  • Proof by Contradiction

Class 6: Continuing Contradictions

  • Finishing the proof of the Odd-Not-Even Lemma
  • Irrational Numbers
  • Proof that the square root of 2 is irrational

Class 7: Contradicting Euclid

  • Continuing Irrational Numbers
  • Defining divides and prime
  • Euclid’s Lemma

Class 8: Concluding Contradictions

  • Preparing for Test 1
  • Proof by Contradiction Practice
  • Least Positive Rational

Class 9: Review

  • Studenting
  • Proof Methods
  • Practice Problems

Class 10: Test 1

Class 11: Comprehending Sets

  • Defining Sets
  • Operations on Sets
  • Building Sets
  • Sets in Python!

Class 12: Quantifiers and Sets

  • Quantifiers
  • Negating Propositions with Quantifiers
  • Defining Set Operators

Class 13: Snow Day!

Class 14: Cardinality of Finite Sets

  • Defining Set Cardinality
  • Binary Relations

Class 15: Sets with Power!

  • Reviewing Binary Relations
  • Connections between relation properties and set sizes
  • Power sets

Class 16: Unnatural Numbers

  • Power sets
  • Practice with binary relations and set properties
  • Defining the natural numbers unnaturally

Class 17: From Sets to Everything (or at least 2+2)

  • Natural numbers from sets
  • Operations on the natural numbers: 2+2=4

Class 18: Review for Test 2

Class 19: Test 2

Class 20: Well Ordering

  • Ordering Sets
  • Well Ordering
  • Proofs using the Well Ordering Principle

Class 21: Proving Well Ordering

  • Well Ordering
  • Proofs using the Well Ordering Principle

Class 22: Weller Ordering

  • Revisiting the Well-Ordered Definition
  • Are all ordered finite sets well ordered?

Class 23: ω, Z, ZF, ZFC, and Zero

  • ω (omega)
  • Z, ZF, ZFC and the General Well Ordering Theorem
  • Is Zero a Natural Number?

Class 24: Induction Principle

  • Story so Far and Where We are Going
  • Induction Principle
  • Proofs using the Induction Principle

Class 25: Proofs using the Induction Principle

  • Gauss Sum
  • Power set size

Class 26: Power of Induction Proofs

  • Finishing the power set size proof

Class 27: Induction Takeaways

  • Defining the takeaway game
  • Proof that takeaway always finishes

Class 28: Stronger (?) Induction

  • Proofs using stronger induction
  • Winning the Takeaway game

Class 29: Induction and Well Ordering Principle

  • Betable Numbers (by Well Ordering Principle and by Induction Principle)

Class 30: Review for Test 3

  • Review for Test 3
  • Practice Problems
  • Flavors of Induction

Class 31: Test 3

Class 32: Infinite Sets

  • Infinite Sets
  • Cardinality of infinite sets
  • Countable Sets

Class 33: Countably Infinite Sets

  • Infinite and Countable Sets
  • Review of Binary Relations
  • All Finite Sets are Countable
  • The Integers are Countably Infinite

Class 34: Beyond Countable Infinities

  • \( \mathbb{N} \times \mathbb{N} \) and \( \mathbb{Q} \) are Countably Infinite
  • Finite and Infinite Binary Strings
  • Uncountably Infinite

Class 35: Cantor’s Paradise

  • Potential and Actual Infinities
  • English is a Disaster
  • Definiting Infinite, Countable, Uncountable, Countably Infinite
  • Proofs of Countability and Uncountability

Class 36: Proving Uncountability

  • Explaining the Rest of the Semester
  • Proofs of Uncountability
  • Diagonalization Proofs
  • Cantor’s Diagonalization Proof (1891)

Class 37: Power of Uncountability

  • Review: Proving Uncountability
  • Infinite Binary Strings (recap)
  • \( \pow(\mathbb{N}) \)
  • Python programs
  • Real numbers

Class 38: Cantor’s Theorem

  • Uncountability of the Real Numbers
  • Cantor’s Theorem
  • Proving Cantor’s Theorem

Class 39: Review

  • Completing Proof of Cantor’s Theorem
  • Review for Test 4