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AI-assisted proof of optimal packing for 11 squares

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In short

The AI-assisted verification of the optimal packing for 11 squares has been completed, achieving native numerical certificates with all 7,920 local Lean modules verified, ensuring the proof's integrity and accuracy.

Key points

  • The AI-assisted verification process has been completed, ensuring the proof's integrity a…: The AI-assisted verification process has been completed, ensuring the proof's integrity and accuracy.
  • The optimal side length for 11 squares is \( T = \frac{6u+4}{1+2u-u^2} \), where \( u \)…: The optimal side length for 11 squares is \( T = \frac{6u+4}{1+2u-u^2} \), where \( u \) is the unique root in \( \left( \frac{9}{25}, \frac{37}{100} \right) \) of \( 5u^8 - 10u^7 - 2u^6 + 14u^5 + 12u^4 - 6u^3 + 2u^2 + 2u - 1 = 0 \).
  • The construction attains approximately 3.8770835900228141773, allowing arbitrary orientat…: The construction attains approximately 3.8770835900228141773, allowing arbitrary orientations, legal boundary contact, and disjoint open interiors.

The complete optimality proof passed verification with native numerical certificates.

The completed EvolvingPrograms verification run

accepted all 7,920 local Lean modules, and its final audit reports zero

admissions. This repository imports those exact proof sources and pinned

build configuration from commit 1bf942a7af1ea330e95489d8997deebd4227ca71

.

See the verification report for evidence and scope.

Selected expensive, exact numerical certificate checks use native_decide

.

Geometry, checker soundness, and proof assembly retain ordinary Lean proofs.

Consequently the final theorem trusts Lean's kernel and native compiler;

this is not a kernel-only verification claim. The approved numerical declarations

and their exact source hashes are recorded in

verification/native-certificates.json.

The optimal side length is

[ T = \frac{6u+4}{1+2u-u^2}, ]

where u

is the unique root in (9/25,37/100)

of

[ 5u^8-10u^7-2u^6+14u^5+12u^4-6u^3+2u^2+2u-1=0. ]

The construction attains approximately 3.8770835900228141773

. The model allows

arbitrary orientations, legal boundary contact, and disjoint open interiors.

The public statements in ElevenSquare/Optimality.lean

and the complete T03

source tree are unchanged from this repository's previous main branch.

File | Purpose |

---|---|

ElevenSquare/Foundations.lean |

Geometry, exact endpoint, attaining construction, closed-cell cover, and finite case reduction. |

ElevenSquare/Pending/ |

Original public interfaces, now discharged by the integrated proof. The directory name is historical. |

ElevenSquare/Interop/Wand125/ |

Connections to the incorporated upstream certificate results. |

ElevenSquare/Tasks/ |

Geometric arguments, checkers, certificate data, and local analytic proofs. |

Sqpack/ |

Incorporated certificate checkers, generated proofs, and simplifications. |

ElevenSquare/Optimality.lean |

Unconditional optimality and side-length lower-bound theorems. |

ElevenSquare/Verification.lean |

Axiom queries for the public proof targets. |

The project pins Lean 4.34.1 and Mathlib revision

d13f23b723b8a846827a245b89c10fc7d3f11612

. Keep lake-manifest.json

unchanged.

On Linux with Python 3, Git, curl, and tar:

bash scripts/run_verification.sh --bootstrap --jobs 2

On macOS, first install the elan

launcher, then use the same command. The

bootstrap can prepare the pinned toolchain and dependency cache when elan

is

already installed. Choose a worker count appropriate to the machine; modules

are compiled serially. Existing valid receipts are reusable. Add --fresh

to

force a complete replay; Ctrl-C stops the runner cleanly.

The command checks every local module and performs the final source, receipt,

dependency, and axiom audit. Require OPTIMALITY_PROVED_WITH_NATIVE_CERTIFICATES

,

zero admissions, and trust_model: lean_kernel_and_native_compiler

in the final

result. Reaching 100% of compiled modules alone is not sufficient.

A source-only check, without Lean, is:

python3 scripts/check_sources.py

The manual workflow and Ubuntu instructions also support resumable verification. Pushes do not start a workflow. The successful source run used EvolvingPrograms' larger runner; it does not establish a cold-build runtime or a 2–3 hour macOS guarantee.

Do not run historical materialization commands or verify.py --setup

on this

snapshot: they restore superseded generated sources. Build objects and logs

belong in ignored .lake/

and .verification/

directories.

We thank EvolvingPrograms, @ctjlewis, and every project contributor for the formalization and verification work. See ACKNOWLEDGEMENTS.md for individual and upstream credits, PROVENANCE.md for source history, and integrations/wand125 for retained notices. Historical simplification notes and partial-audit records are preserved; their old unfinished-status statements are superseded by the completed-run report.

Original source: github.com

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