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🧩 Challenges · Discrete Mathematics II — Combinatorics

Build it, break it, predict it, or recall it. Pick a challenge and prove you've got it.

📅 Today's Daily Challenge 🏆 Leaderboard

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recall a repeated objects permutation formula

recall

easy medium hard

recall an arrangement formula

recall

easy medium hard

recall a catalan or lattice path formula

recall

easy medium hard

recall the pigeonhole bound

recall

easy medium hard

recall a first order recurrence closed form

recall

easy medium hard

recall the fibonacci generating function

recall

easy medium hard

recall a chromatic polynomial

recall

easy medium hard

recall a closed form sum

recall

easy medium hard

recall the multinomial coefficient

recall

easy medium hard

recall eulers totient formula

recall

easy medium hard

recall binets formula

recall

easy medium hard

recall the geometric power series

recall

easy medium hard

recall a composition count for partitions

recall

easy medium hard