Personal Notes On Elementary Combinatorial Techniques [Unofficial]

• Principle of Addition
• Principle of Multiplication
• Counting Permutations 
• Counting Combinations (WIth or without repetitions)
• Binomial Coefficients
• Bijection
• Partitions
• Recurrence Relations
• Counting in terms of smaller instances of the same problem
• Principle of Inclusion and Exclusion
• Overlapping sets 
• Generating Function
• Polya's Method
• Graph Theory

Proof techniques

• Mathematical Induction
• Universal Proof 
• Pigeonhole Principle
• Existential Proof

References

1. How Mathematics Has Got Broader With Time
2. Personal Notes On Areas Of Mathematics [Unofficial]
3. Areas Of Mathematics I Am Learning
4. Personal Notes On Number Theory [Unofficial]
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