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Discrete
Discrete Mathematics
Logic, sets, counting, graphs, modular arithmetic. Later headings open after the one before. Prove and compute with logic, sets, combinatorics, graphs, and modular arithmetic as a CS discrete-math course does.
- 6 headings
- Ladder
- Test out a heading you have
Free to start. Sign in with Google or email.
A class on this path
Logic and proof · First class
Pick where you want to start
Each heading is its own course. Later ones open when you finish — or skip — the one before. A later course does not reteach earlier bands.
Logic and proof
Start hereTranslate English into propositions and predicates, and write a direct, contrapositive, or induction proof.
Sets and functions
After Logic and proof — test out to unlockWork unions, images, and injections/surjections, and count a finite set with inclusion-exclusion when needed.
Combinatorics
After Sets and functions — test out to unlockChoose permutations vs combinations, including with repetition, on a worded counting problem.
Graphs
After Combinatorics — test out to unlockUse degree, paths, trees, and bipartite checks, and run BFS/DFS on a small graph by hand.
Recurrence
After Graphs — test out to unlockSet up a recurrence from a process and unwind or solve a linear one.
Modular arithmetic
After Recurrence — test out to unlockCompute with mod, inverses, and a simple RSA-style or hashing example.
What this is for
- 01
Translate English into propositions and predicates, and write a direct, contrapositive, or induction proof.
- 02
Work unions, images, and injections/surjections, and count a finite set with inclusion-exclusion when needed.
- 03
Choose permutations vs combinations, including with repetition, on a worded counting problem.
Why a path, not a playlist
Logic, sets, counting, graphs, modular arithmetic. Later headings open after the one before.
Each heading is its own course with a tutor. Later headings open when you finish — or test out of — the one before.
After you sign in
- •You land on this map — every heading is already there.
- •Take the open class, or test out of a later heading to unlock it.
- •Each heading is one shared course — same syllabus and first class for everyone. Later classes continue on your copy.