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A MATHEMATICAL ADVENTURE FOR CURIOUS MINDS

A small why. A big adventure.

Follow the story. Try a proof. Let curiosity choose how deep you go.

No account. No API key. Just curiosity.

Two ways in. One table between them.

I'd rather not fight math today

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 mathematics

Begin 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.

Start with “I don’t know yet.”

Seventeen chapters, one extraordinary argument. One small discovery is enough for today.

17 chapters · MathOriginal source ↗

Pip’s rule: mistakes are clues. Every chapter is open, and every question allows another try.

Modularity, the 3–5 trick, and compatible pieces.

Choose your depthDefinitions, assumptions, mechanisms.
Explore the whole proof29,511 theorems · original statements · dependencies

Search the local catalogue in English or Japanese. Major landmarks have Japanese titles. Open the full original proof on GitHub for the complete context.

Your discovery in this chapter

Understand why finding a modular form modulo three is a useful beginning, even though it is not the ending.

Weight
A parameter in the transformation law of a modular form.
Congruent coefficients
Coefficients agree after reduction by the specified prime ideal.
Where the metaphor ends

Notes represent arithmetic coefficients, not literal sound. The weight-one and weight-two labels are mathematical transformation laws, not musical volume.

</>S_WeierstrassCurve_isResiduallyModular_three_and_noInertiaFixedTorsion_and_not_cube_dvd_of_isSemistableModel.lean
Original source ↗ · L67–84Pinned revision aa2d8b3
theorem solution
(W : WeierstrassCurve ℤ) (hΔ : W.Δ ≠ 0) (hW : W.IsSemistableModel)
(h3 : W.ModRepIsIrreducible 3) :
∃ M : ℕ, 0 < M ∧ W.IsResiduallyModularOfLevel 3 M ∧
(∀ q : ℕ, q.Prime → q ≠ 3 → ¬ q ^ 3 ∣ M) ∧
(3 ^ 2 ∣ M →
∀ A : ValuationSubring (AlgebraicClosure ℚ), A.LiesOverPrime 3 →
∀ x : Submodule.torsionBy ℤ
((W.map (Int.castRingHom ℚ))⁄(AlgebraicClosure ℚ)).Point (3 : ℕ),
(∀ σ ∈ A.inertiaSubgroupIn ℚ, σ • x = x) → x = 0) := by
obtain ⟨N, hNZ, a, hbasis, heig, hreal, hcube, htr, hns⟩ :=
haveI : NeZero N := hNZ
refine ⟨N, Nat.pos_of_ne_zero hNZ.out, ?_, hcube, hns⟩
obtain ⟨f, hf, 𝔪', h𝔪max, h𝔪3, hcong⟩ :=
hbasis heig hreal
refine ⟨f, 𝔪', hf, h𝔪max, h𝔪3, ?_⟩

👩🏻‍🎨 Mika · Source reading guide

Under nonsingularity, semistability and mod-three irreducibility, the theorem returns residual modularity at a positive level M, plus restrictions on prime cubes and inertia-fixed torsion. The weight-one input comes from the specialized octahedral Langlands–Tunnell route. Multiplication by an Eisenstein series and Deligne–Serre lifting occur in the dependencies that supply the weight-two eigenform.

Annotated original · not a live Lean state

Point to a story clue or a highlighted term to connect the two.

Try this logical move →
Source and verification details

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 & attribution
Chapter 10/17 · Math

A three-note audition

Pip confuses a modular fingerprint with a very short national anthem.

How we got here

The previous chapter gave the strategy. The first entrance uses information modulo 3. A result about that small representation supplies a starting point; lifting is a separate step with extra conditions.

These links explain the reading route. A story analogy is not a proof of this theorem.

Take it to the tea salon
PIP
“I can play three notes. How do we get from a little tune to the whole concert?”
A tiny audition

Story → proofPip’s three-note audition introduces the residual-modularity route; the positive-level hypothesis still has to be supplied.

A positive level0 < M
MIKA
“First compare the number data in the residue setting. We also need conditions on the level, which specifies the allowed transformations.”
Keep the conditions

Story → proofThe condition sheet accompanies the tune. In particular, the level must not be divisible by q cubed.

Keep the conductor condition¬ q ^ 3 ∣ M

The idea behind the story

Under nonsingularity, semistability and mod-three irreducibility, the theorem returns residual modularity at a positive level M, plus restrictions on prime cubes and inertia-fixed torsion. The weight-one input comes from the specialized octahedral Langlands–Tunnell route. Multiplication by an Eisenstein series and Deligne–Serre lifting occur in the dependencies that supply the weight-two eigenform.

Does weight mean how loud a form sounds?

  • No. It specifies a mathematical transformation law.
  • Yes. Weight two is twice as loud.

The story and source are readable here. Enable JavaScript to edit proofs, try quizzes, and explore the interactive map.

If the first route is blocked, another curve can lend us the fingerprint we need.

Read. Try. Make it click.

  1. Read the manga and choose Story, Math, or Lean depth.
  2. Open the proof playground. Edit the tactics and watch the goals change.
  3. Select a state, term, or hint. Wrong turns are part of the story.

The playground checks a small propositional language. FLT excerpts are editable reading material, not live-checked Lean proofs. The complete FLT build remains an upstream verification report.

I’m lost · Help

Mika’s help desk

A three-note audition

One thing at a time

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.

In simpler words

You do not need to know Lean, symbols or university mathematics to begin. Definitions come first in the small stories.

A small clue

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 →