Follow the story. Try a proof. Let curiosity choose how deep you go.
Walk in through the manga: seventeen chapters, sixty-four pocket pebbles, zero required formulas. The Lean source stays behind glass until you ask for it.
Straight to the mathematicsBegin at the proof map — thousands of named theorems — then climb the full ladder from clock inverses to R = T. The story keeps telling itself beside you; it will keep you honest.
Made for company: one reader who loves math and one who does not — one sofa. Whatever each of you finds carries over to the tea salon.
Seventeen chapters, one extraordinary argument. One small discovery is enough for today.
Pip’s rule: mistakes are clues. Every chapter is open, and every question allows another try.
Why the curve’s arithmetic cannot split the wrong way.
Search the local catalogue in English or Japanese. Major landmarks have Japanese titles. Open the full original proof on GitHub for the complete context.
The exponent here is restricted to five, seven or thirteen. Each case already has a proved result. Instead of rebuilding every argument, we apply the matching result to the hypothetical package. No package survives those cases.
Annotated original · not a live Lean statePoint to a story clue or a highlighted term to connect the two.
Try this logical move →Source: anthropics/fermats-last-theorem @ aa2d8b3. Upstream reports verification; this reader has not independently rebuilt the project. Manga explanations are not formal proofs.
Source license & attributionThe oldest folders in the archive still know a few tricks.
The symmetry branch needs earlier mathematical results for its cases. We have already seen a separate case file for exponent 3. Here older results become tools; this is a return to that branch, not a new counterexample.
These links explain the reading route. A story analogy is not a proof of this theorem.
Already familiar? Keep reading. Otherwise, open a word or follow the prerequisites from the beginning.
Story → proofThe archive drawer holds earlier results for a restricted suspect list: exponents five, seven and thirteen.
Three possible suspectsP.p = 5 ∨ P.p = 7 ∨ P.p = 13Story → proofThree folder piles are the three alternatives of ∨. rcases opens a separate branch for each one.
One case at a timercases hp with h | h | hStory → proofShrinking boxes evoke descent, but this excerpt borrows the already proved exponent-five theorem; it does not replay descent.
Borrow the result for fivefermatLastTheoremFiveStory → proofBorrowing the closed folders means reusing proved results. The thirteen theorem closes one of the remaining branches.
Borrow the result for thirteenfermatLastTheoremThirteenThe exponent here is restricted to five, seven or thirteen. Each case already has a proved result. Instead of rebuilding every argument, we apply the matching result to the hypothetical package. No package survives those cases.
The story and source are readable here. Enable JavaScript to edit proofs, try quizzes, and explore the interactive map.
Short scenes. Real logical goals. A pigeon who is very invested in your success.
Opening the casebook…
The veterans’ cabinet
Start with the cake-scale story. You only need to read one small piece at a time. If you are in the Fermat story, start with Story depth, then the words listed before the chapter.
You do not need to know Lean, symbols or university mathematics to begin. Definitions come first in the small stories.
Look at the small example before the general formula. Ask what changed and what stayed the same.
Close this panel to return to the exact place you were reading. These are prepared hints for this page.
Start with the first small story →