This is a repository I made for posterity in summer 2022 as I was learning combinatorics myself.
Currently, it doesn't contain anything substantial but here are the topics that I would like to write about (hopefully) over the next few months (May to August 2022).
Introduction to basic counting techniques, combinations, permutations, orderings, and counting principles. Emphasis on interpretation over strings and sets. Elementary number theory results. Binomial coefficients.
Recurrences and induction. Lattice paths. Catalan numbers. Binomial theorem.