Discrete Mathematics with Applications - Metric Edition (Epp) Chapter 9
https://www.cs.yale.edu/homes/aspnes/classes/202/notes.pdf Chapter 6, 11, 12
https://www.cs.carleton.edu/faculty/dln/book/ch09_counting_2021_September_08.pdf
https://www.cs.carleton.edu/faculty/dln/book/ch10_probability_2021_September_08.pdf
https://runestone.academy/ns/books/published/DiscreteMathText/chapter9.html
https://runestone.academy/ns/books/published/DiscreteMathText/probability9-1.html
https://runestone.academy/ns/books/published/DiscreteMathText/multrule9-2.html
https://runestone.academy/ns/books/published/DiscreteMathText/additionrule9-3.html
https://runestone.academy/ns/books/published/DiscreteMathText/pigeonhole9-4.html
https://runestone.academy/ns/books/published/DiscreteMathText/combinations9-5.html
https://runestone.academy/ns/books/published/DiscreteMathText/binomial9-6.html
https://runestone.academy/ns/books/published/dmoi-4/ch_counting.html
https://runestone.academy/ns/books/published/dmoi-4/sec_counting-pascal.html
https://runestone.academy/ns/books/published/dmoi-4/sec_counting-combine-outcomes.html
https://runestone.academy/ns/books/published/dmoi-4/sec_counting-non-disjoint.html
https://runestone.academy/ns/books/published/dmoi-4/sec_counting-combperm.html
https://runestone.academy/ns/books/published/dmoi-4/sec_counting-multisets.html
https://runestone.academy/ns/books/published/dmoi-4/sec_comb-proofs.html
https://runestone.academy/ns/books/published/dmoi-4/sec-counting-probability.html
https://runestone.academy/ns/books/published/dmoi-4/sec_advPIE.html
https://runestone.academy/ns/books/published/dmoi-4/sec_count-conc.html
https://runestone.academy/ns/books/published/ads/chapter_2.html
https://runestone.academy/ns/books/published/ads/s-the-rule-of-products.html
https://runestone.academy/ns/books/published/ads/s-permutations.html
https://runestone.academy/ns/books/published/ads/s-partitions-and-law-of-addition.html
https://runestone.academy/ns/books/published/ads/s-combinations-and-the-binomial-theorem.html