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Mathematics
Group Theory
1. Introduction to Algebraic Structures
2. Definition of a Group
3. Fundamental Examples of Groups
4. Order of Elements and Groups
5. Subgroups
6. Cyclic Groups
7. Permutation Groups
8. Cosets and Lagrange's Theorem
9. Normal Subgroups and Quotient Groups
10. Group Homomorphisms
11. The Isomorphism Theorems
12. Group Actions
13. The Sylow Theorems
14. Direct Products and Sums
15. Structure of Finite Abelian Groups
16. Solvable and Nilpotent Groups
17. Composition Series and Jordan-Hölder Theorem
18. Free Groups and Presentations
19. Semidirect Products
20. Introduction to Representation Theory
21. Applications of Group Theory
Direct Products and Sums
External Direct Product
Definition and Construction
Properties of External Direct Products
Order of Elements in Direct Products
Subgroups of Direct Products
Internal Direct Product
Definition and Conditions
Recognition Theorem
Relationship to External Direct Product
Direct Sum of Abelian Groups
Definition for Abelian Groups
Relationship to Direct Product
Infinite Direct Sums
Decomposition Theorems
Unique Factorization
Indecomposable Groups
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13. The Sylow Theorems
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15. Structure of Finite Abelian Groups