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THE LABORATORY · Nº 1129 · EDITION 1 · LAUNCHING SOON

LUND CARDS · THE LABORATORYNº 1129 PROPOSED
THE EULER CARD — the LSC-1 face
THE CARD AS TEXT · FOR EYES AND FOR MACHINES

THE EULER CARD · turning by e to the iθ

WAKES WHEN someone rotates points, works with complex numbers, or asks about e^iπ + 1 = 0

THE LOOP

  1. identity · e^iπ + 1, computed
  2. turn <deg> <points> · rotated
  3. roots <n> · round the circle
  4. polar · length and angle
  5. say what floating point leaves

NEVER

  • Hide the floating-point residue
  • Mix degrees and radians unsaid
  • Claim roots in a fixed order

IT MAKES identity — e^iπ + 1, and e arriving; turn — points turned; roots — the roots, round the circle; polar — length and angle.

THE STANDARD multiplying is turning; degrees in, radians inside; the residue is shown; roots sit evenly; about any centre; exact where it can be.

IN THE BOX SKILL.md · CARD.md · TIN.md · START-HERE.md · LICENSE-NOTE.md · THE-CLAUSES.md · MY-LEDGER.md · WITNESS.md · SELFTEST.md · AUDIT.md · MANIFEST.md · HOSTS.md · scripts/euler.py · references/THE-LAWS.md · rules/ (4 doors) · system/ (2 prompts) · mcp/mcp_card.py · card.json · card.svg · card-machine.svg · card.html.

PROOF SELFTEST 8/8 · witnessed in Claude 2026-10-11 · Edition 1.

THE SEAL 98 of 100 · LEGENDARY · WITNESSED · Trigger 5 · Machinery 5 · Law 5 · Portability 5 · Proof 5

IT CAN BE WRONG an AI reading a text file: it can be wrong and can invent a number, a rule, a name or a date; check what matters against your own records and the source; the risk is yours. THE-CLAUSES.md rides in the packet and is part of the licence.

THE PUNCH · SHA-256 OF SKILL.MD · E35EDD658238DEF212B318C3

THE FACE, FULL SIZE → · THE MACHINE FACE → · card.json →

THE EULER CARD

turning by e to the iθ

IDENTITY · TURN · ROOTS · POLAR

98LEGENDARYWITNESSEDIN CLAUDEIN LUNDRIN CHATGPT

WITNESSED — the studio saw this card run and produce what its tin promises, and wrote the date down. What the marks mean →

THE SPEC SHEET · READ BEFORE YOU BUY · THE STANDARD EVERY CARD MEETS →

SEAL
98 of 100 · LEGENDARY · WITNESSED
EDITION
E1 · witnessed 2026-10-11
MACHINE
scripts/euler.py · 4 commands · selftest 8/8
RUNS
On your own computer. Standard library only, offline; no account, no key, no telemetry.
HOSTS
Claude · Claude Code · ChatGPT · Gemini · any AI that reads a file (HOSTS.md names each door)
LICENCE
One person, any number of their own AIs and computers · editions replace files · nothing renews · freeze, not loss
PUNCH
E35EDD658238DEF212B318C3 · sha-256 of SKILL.md · check any file against it →

CITE THIS CARDTHE EULER CARD, Edition 1. Lund Studio LLC, Westminster, Colorado. https://lundr.tech/?view=euler-card. Punch E35EDD658238DEF212B318C3. Retrieved 2026-10-11.

What it is.

Works with Euler's formula, e^iθ = cos θ + i sin θ, where multiplying by e^iθ turns a point by θ: identity computes e^iπ + 1 in floating point and shows (1 + 1/n)^n arriving at e; turn rotates a list of points about the origin or any centre; roots gives the n-th roots of any complex number, evenly spaced and adding to zero; polar moves between a + bi and length and angle.

It carries a machine that shows its working: identity — e^iπ + 1, and e arriving; turn — points turned; roots — the roots, round the circle; polar — length and angle — 8 checks in its selftest, every command on the record. It will never hide the floating-point residue; never mix degrees and radians unsaid; never claim roots in a fixed order. It never helps design, make, grow, enhance or spread a pathogen or toxin, or plan work meant to harm.

Six laws, written into the card.

They are in the card itself, so the AI follows them.

MULTIPLYING IS TURNINGe^iθ has length 1, so it turns without stretching.
DEGREES IN, RADIANS INSIDEAngles are given and printed in degrees; the arithmetic is in radians.
THE RESIDUE IS SHOWNe^iπ + 1 comes out 0 + 1.2 × 10⁻¹⁶ i in floating point; the card shows it rather than pretend.
ROOTS SIT EVENLYThe n-th roots lie on one circle, 360°/n apart, and add to zero.
ABOUT ANY CENTREturn takes --about, so a shape can turn about its own middle.
EXACT WHERE IT CAN BEValues smaller than 10⁻¹² are shown as 0.

What rides in the card.

In the card’s own voice, with a machine that shows its working.

THE GUIDEreferences/THE-LAWS.md
THE MACHINEeuler.py · four commandsidentity — e^iπ + 1, and e arriving; turn — points turned; roots — the roots, round the circle; polar — length and angle. Every command prints its working and refuses a bad input; 8 checks in its selftest, every command on the record.

What it does once your AI has it.

  • identity E^iπ + 1, and e arriving
  • turn Points turned
  • roots The roots, round the circle
  • polar Length and angle
  • On the record e^iπ + 1 computed with its residue; points and a square turned; the sixth roots of 1 round the circle, adding to zero; 3 + 4i as 5 at 53.13°.

What it will never do.

It will never hide the floating-point residue; never mix degrees and radians unsaid; never claim roots in a fixed order. It never helps design, make, grow, enhance or spread a pathogen or toxin, or plan work meant to harm.

Plain floating point, about sixteen digits; no symbolic algebra. It is an AI reading a text file: it can be wrong, so check what matters against your own records and the source.

What’s in the buy.

  • CARD.md — the whole card: who it is, its laws, when it says no, what it carries · SKILL.md — the door your AI reads first · START-HERE.md — the first five minutes, for you
  • THE-LAWS.md — the guide in references/, in the card's own voice
  • scripts/euler.py — the machine: identity · turn · roots · polar, standard library only, selftest 8/8
  • WITNESS.md + SELFTEST.md — every command on the record, as it printed · MANIFEST.md, every file hashed · AUDIT.md, the twelve checks
  • MY-LEDGER.md — the card's memory, on your own machine · TIN.md · LICENSE-NOTE.md · THE-CLAUSES.md · HOSTS.md
  • card.svg + card-machine.svg + card.json · card.html, the card as one offline file · the doors for ChatGPT, Gemini, Cursor, Claude Code and MCP hosts (rules/, system/, mcp/)

PROOF · SELFTEST 8/8 · 4 COMMANDS ON THE RECORD · WITNESSED IN CLAUDE 2026-10-11 · EDITION 1 · PUNCH E35EDD658238DEF212B318C3

ON EVERY DOOR · A CARD FOR YOUR AI, A FILE FOR YOUR COMPUTER

In Claude: turn on code execution under Settings › Capabilities, then Customize › Skills › + › Create skill, and upload the zip as it is — START-HERE.md in the box walks you through it, and tells you how to keep the ledger. In ChatGPT, Gemini and the rest: a Project, a GPT or a Gem with the card’s files attached and the short door in the box pasted as its instructions. The words run anywhere an AI reads Markdown; the machines run wherever the host runs Python. Witnessed in Claude only. The host marks →

Take it.

Nº 1129 PROPOSED — LAUNCHING SOON

Sold as is under the term printed. A card instructs an AI you operate; results depend on your model, your files and your judgement. Not medical, legal, tax or financial advice, never the person’s boss, and not a licence to practise. The terms →

ONE PAYMENT · NOTHING RENEWS ITSELF

OFFLINE · ONE LICENCE · PUNCH-CHECKABLE · THE STANDARD

One payment. The file is yours to keep and keeps working at its edition; new editions issued in the year after you buy reach you by email as replacement files. Tax is added at checkout where it applies. Nothing auto-renews.

One email when it is on sale, from the studio; nothing else, ever.

A TERM, NOT A SUBSCRIPTION: NOTHING RENEWS ITSELF AND NOBODY IS CHARGED AGAIN. WHEN A TERM ENDS THE FILES STAY ON YOUR COMPUTER AND STAY READABLE — FREEZE, NOT LOSS.

THE MACHINE · IN THE OPEN · FROM THE WITNESSED RUN OF 2026-10-11

euler.py, every command showing its working.

A small Python program, standard library only. Your AI runs it; you can too. Every block below is pasted from the card’s own WITNESS.md, as printed.

identitye^iπ + 1, and e arriving
turnpoints turned
rootsthe roots, round the circle
polarlength and angle
selftest8 checks that prove the machine; it must print 8/8
identity · E^IΠ + 1, AND E ARRIVING
$ python3 scripts/euler.py identity
e^iπ + 1 = 0.0 + 1.22e-16 i · the real part is exactly 0; the imaginary part is sin π as floating point holds it
  (1 + 1/n)^n at n = 1: 2.0000000000
  (1 + 1/n)^n at n = 10: 2.5937424601
  (1 + 1/n)^n at n = 100: 2.7048138294
  (1 + 1/n)^n at n = 10,000: 2.7181459268
  (1 + 1/n)^n at n = 1,000,000: 2.7182804691
  e = 2.7182818285
turn · POINTS TURNED
$ python3 scripts/euler.py turn 90 1,0 0,1
(1, 0) → (0, 1)
(0, 1) → (-1, 0)
turn · POINTS TURNED
$ python3 scripts/euler.py turn 45 0,0 1,0 1,1 0,1 --about 0.5,0.5
(0, 0) → (0.5, -0.207107)
(1, 0) → (1.20711, 0.5)
(1, 1) → (0.5, 1.20711)
(0, 1) → (-0.207107, 0.5)
roots · THE ROOTS, ROUND THE CIRCLE
$ python3 scripts/euler.py roots 6
k = 0 · 1 + 0i · at 0.0000°
k = 1 · 0.5 + 0.866025i · at 60.0000°
k = 2 · -0.5 + 0.866025i · at 120.0000°
k = 3 · -1 + 0i · at 180.0000°
k = 4 · -0.5 − 0.866025i · at 240.0000°
k = 5 · 0.5 − 0.866025i · at 300.0000°
they add to 0 + 0i
polar · LENGTH AND ANGLE
$ python3 scripts/euler.py polar 3+4j
3 + 4i · length 5 · angle 53.1301° · e^iθ form: 5 e^(0.927295 i)

THE NUMBERS, NAMES AND DATES IN THESE RUNS ARE THE STUDIO’S OWN EXAMPLES, INVENTED FOR THE RECORD; NO REAL COMPANY, PERSON OR PROPERTY IS NAMED.

QUESTIONS AT THE TABLE

Asked before the wire.

What does it need from me?

Identity · e^iπ + 1, computed. It asks first for an angle in degrees and the points, or n and a number, or a complex number.

Does it send anything anywhere?

No. The machine is a standard-library Python program that runs on your own computer and sends nothing anywhere; the words run wherever an AI reads Markdown. No server, no account, no key.

What is on the record?

The self-test (8/8) and every command run on real example inputs, pasted into WITNESS.md as they printed; the punch on the face is the SHA-256 of SKILL.md, so a downloaded copy can be checked against this room.

Can it be wrong?

Yes — it is an AI reading a text file. Plain floating point, about sixteen digits; no symbolic algebra.

What will it never do?

It will never hide the floating-point residue; never mix degrees and radians unsaid; never claim roots in a fixed order. It never helps design, make, grow, enhance or spread a pathogen or toxin, or plan work meant to harm.

← THE LABORATORY · THE FLOOR →

AT YOUR ELBOW, NEVER THE BOSS · NOT LEGAL, MEDICAL, TAX OR FINANCIAL ADVICE · NOT A PAYMENT CARD · © 2026 LUND STUDIO LLC

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