# Introduction to Algebraic Structures

- Institution: IISc Bangalore
- Department: Mathematics
- Taught by: Prof. Mahesh Kakde, Prof. R. Venkatesh
- Level: Undergraduate
- Language: English
- Subjects: Mathematics
- Source: [NPTEL](https://nptel.ac.in/courses/111108001)
- Licence: [CC BY-NC-SA](https://nptel.ac.in/faq) (Non-commercial use only.)
- Syllabus: [at the source](https://nptel.ac.in/courses/111108001)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

This course aims to offer an accessible introduction to algebraic structures to undergraduate students, exploring foundational topics such as set theory, combinatorics, graph theory, number theory, and group theory. It presents fundamental counting techniques and applies them to solve introductory counting problems, including those related to graphs. Gradually, the course transitions into basic number theory and introduces the concept of groups, using examples derived from combinatorics and number theory to provide a deeper understanding of these mathematical structures. This course does not require any prior knowledge of mathematics.

Intended audience: UG level course

## Lectures

1. [Introduction to mathematics and set theory](https://invisiblenetwork.ai/learn/nptel/111108001/6205b48b9764) (YouTube)
2. [Set identities, Cartesian product, relations and functions](https://invisiblenetwork.ai/learn/nptel/111108001/c9ef88f9a2b6) (YouTube)
3. [Logic and construction of new sets](https://invisiblenetwork.ai/learn/nptel/111108001/59fbd36602d3) (YouTube)
4. [Functions](https://invisiblenetwork.ai/learn/nptel/111108001/c4eaf2152724) (YouTube)
5. [Properties of functions](https://invisiblenetwork.ai/learn/nptel/111108001/2ec2d19e9aa0) (YouTube)
6. [Composing functions and Cantor's theorem](https://invisiblenetwork.ai/learn/nptel/111108001/ad5147c241fd) (YouTube)
7. [Don Zaiger's proof: Primes of the form 4k+1 can written as sum of two squares.](https://invisiblenetwork.ai/learn/nptel/111108001/4a2a042d6695) (YouTube)
8. [Axiom of choice and Paritition of a set.](https://invisiblenetwork.ai/learn/nptel/111108001/3e2c79af1863) (YouTube)
9. [Correspondence between partitions of a set and equivalence relations on it.](https://invisiblenetwork.ai/learn/nptel/111108001/5e7abf573e65) (YouTube)
10. [Partially ordered sets, well-ordering principle and Zorn's lemma.](https://invisiblenetwork.ai/learn/nptel/111108001/ad48055ddbe8) (YouTube)
11. [Defining natural numbers: Peano axioms.](https://invisiblenetwork.ai/learn/nptel/111108001/a0b30f099ed9) (YouTube)
12. [Order properties of natural numbers and notion of cardinality of a set.](https://invisiblenetwork.ai/learn/nptel/111108001/cbb0f95d2841) (YouTube)
13. [Cardinality of a finite set.](https://invisiblenetwork.ai/learn/nptel/111108001/cd6ac59e2522) (YouTube)
14. [Countable sets](https://invisiblenetwork.ai/learn/nptel/111108001/fa209493eb0a) (YouTube)
15. [Uncountable sets](https://invisiblenetwork.ai/learn/nptel/111108001/57cdd1141ff4) (YouTube)
16. [Schroder-Bernstein theorem](https://invisiblenetwork.ai/learn/nptel/111108001/d83ec6f8e759) (YouTube)
17. [Integers and Rational Numbers](https://invisiblenetwork.ai/learn/nptel/111108001/a8aea5376b8c) (YouTube)
18. [The Construction of Rational Numbers and Counting Principles](https://invisiblenetwork.ai/learn/nptel/111108001/ab6b526fe92e) (YouTube)
19. [Counting in Two Ways](https://invisiblenetwork.ai/learn/nptel/111108001/67296378c926) (YouTube)
20. [Binomial Coefficients and Properties](https://invisiblenetwork.ai/learn/nptel/111108001/6244436808c3) (YouTube)
21. [The Pigeonhole Principle](https://invisiblenetwork.ai/learn/nptel/111108001/487057e481cf) (YouTube)
22. [Formal Series](https://invisiblenetwork.ai/learn/nptel/111108001/12b3c5dca643) (YouTube)
23. [Formal Series and Applications](https://invisiblenetwork.ai/learn/nptel/111108001/531eafd85c09) (YouTube)
24. [Solving Linear Recurrences](https://invisiblenetwork.ai/learn/nptel/111108001/fdd9cb9a8279) (YouTube)
25. [Principle of Inclusion and Exclusion](https://invisiblenetwork.ai/learn/nptel/111108001/b3bf6e4e74c5) (YouTube)
26. [Möbius Function on Finite Posets](https://invisiblenetwork.ai/learn/nptel/111108001/43fa1f83d768) (YouTube)
27. [Möbius Inversion Formula](https://invisiblenetwork.ai/learn/nptel/111108001/fe89b85f81f0) (YouTube)
28. [Möbius Inversion Formula and Applications](https://invisiblenetwork.ai/learn/nptel/111108001/77364fd95d57) (YouTube)
29. [Introduction to Graph Theory, Graphs and Special Graph Families](https://invisiblenetwork.ai/learn/nptel/111108001/d413da84ab6a) (YouTube)
30. [Graph Representations and Basic Graph Operations](https://invisiblenetwork.ai/learn/nptel/111108001/e41a35ec88a0) (YouTube)
31. [Handshake Lemma and Graph Connectivity](https://invisiblenetwork.ai/learn/nptel/111108001/55d3fe8b9b59) (YouTube)
32. [Cycles, Bipartite Graphs, and Trees](https://invisiblenetwork.ai/learn/nptel/111108001/6c74cee724d3) (YouTube)
33. [Trees and Their Properties](https://invisiblenetwork.ai/learn/nptel/111108001/7d2a2782a017) (YouTube)
34. [Eulerian and Hamiltonian Graphs](https://invisiblenetwork.ai/learn/nptel/111108001/a789d96943f3) (YouTube)
35. [Matchings and Graph Coloring](https://invisiblenetwork.ai/learn/nptel/111108001/9887b3d65df1) (YouTube)
36. [Number theory and divisibility](https://invisiblenetwork.ai/learn/nptel/111108001/acd24844fe2f) (YouTube)
37. [Greatest Common Divisor - I](https://invisiblenetwork.ai/learn/nptel/111108001/4ea72d4fcbfd) (YouTube)
38. [Greatest Common Divisor - II](https://invisiblenetwork.ai/learn/nptel/111108001/0da0ac5fd0b3) (YouTube)
39. [LCM, primes and prime factorisation](https://invisiblenetwork.ai/learn/nptel/111108001/57ac5551a46e) (YouTube)
40. [Consequences of prime factorisation and infinitude of primes](https://invisiblenetwork.ai/learn/nptel/111108001/37431b13423a) (YouTube)
41. [Euler's proof of infinitude of primes](https://invisiblenetwork.ai/learn/nptel/111108001/f65fea29978f) (YouTube)
42. [Congruencies and modular arithmetic](https://invisiblenetwork.ai/learn/nptel/111108001/0a82ff01e33d) (YouTube)
43. [Diophantine equations and residue classes](https://invisiblenetwork.ai/learn/nptel/111108001/3b4cacdf84de) (YouTube)
44. [Solving Diophantine equations in one variable and Chinese remainder theorem](https://invisiblenetwork.ai/learn/nptel/111108001/7a40dd2d6307) (YouTube)
45. [Solving Diophantine equations using CRT](https://invisiblenetwork.ai/learn/nptel/111108001/9b265801e30c) (YouTube)
46. [Proof of Hensel's lemma](https://invisiblenetwork.ai/learn/nptel/111108001/d8b0b53b4e1a) (YouTube)
47. [Introduction to Euler's totient function](https://invisiblenetwork.ai/learn/nptel/111108001/b1d3e026a70d) (YouTube)
48. [More on totient function](https://invisiblenetwork.ai/learn/nptel/111108001/c4dec7feb1d8) (YouTube)
49. [Mobius inversion formula](https://invisiblenetwork.ai/learn/nptel/111108001/7e3babf3e68a) (YouTube)
50. [Euler's theorem](https://invisiblenetwork.ai/learn/nptel/111108001/553acfa6a9cf) (YouTube)
51. [Ring structure on set of residue classes](https://invisiblenetwork.ai/learn/nptel/111108001/a575cf33afd0) (YouTube)
52. [Polynomial ring over a field, division algorithm and consequences.](https://invisiblenetwork.ai/learn/nptel/111108001/b64a6d795689) (YouTube)
53. [Wilson's theorem, Lagrange's theorem and introduction to cyclic groups](https://invisiblenetwork.ai/learn/nptel/111108001/b82ae2ee0fab) (YouTube)
54. [Classification of cyclic unit groups modulo m and proof.](https://invisiblenetwork.ai/learn/nptel/111108001/04a543eea5c4) (YouTube)
55. [Primitive roots modulo m and application in solving linear congruences](https://invisiblenetwork.ai/learn/nptel/111108001/aa979a30675c) (YouTube)
56. [More on solving congruence equations and introduction to quadratic residue and Legendre symbol](https://invisiblenetwork.ai/learn/nptel/111108001/450e4b8ceb80) (YouTube)
57. [Computing Legendre symbol: Euler's criterion and Law of quadratic reciprocity](https://invisiblenetwork.ai/learn/nptel/111108001/6426ceab98fc) (YouTube)
58. [Dirichlet's theorem on primes in AP: Proof of special cases](https://invisiblenetwork.ai/learn/nptel/111108001/e7c444d0e18b) (YouTube)
