T-099: Mixed rectangle-measure lower bound verified at , on a finer declared net
V3 C3 lower bound confirmed superseded by T-102
A rectangle density of wand125/square-packing-bounds, checked at coverage one on a net it declares and published on 6 October 2026, proves = 4.704.
The certificate is a density of 209 uniform rectangles in D4 orbits, and no point mass, of total mass 1799999/100000, on a net it declares itself: core side 1999/2000 and 832 half-angle tangents of step 1/2006, finer than the 416 of step 1/1001 at core 999/1000 that T-096's certificate declares. Since 1999/2000 (1 + 1/2006) = 4011993/4012000 < 1, and the last tangent 831/2006 is past tan(pi/8), every unit square contains a concentric core of side 1999/2000 at a net angle strictly in its interior.
The source reports every such core capturing mass at least one: at all 831 oblique net angles by code/mixed_rotated_verify.cpp, its research copy of Tokoharu's verify.cpp at coverage threshold one, run by the same driver as T-096's certificate changed only to allow more workers, and at the axis by exact integer tables.
The value is above T-096's 47/10, the source's earlier certificate and the reported and verified lower bound at before it, by 0.004, and supersedes it.
The certificate was decided here on 6 October 2026 by sqverify-fast, this repository's clean-room measure verifier, at all 832 directions of the net the candidate declares, and two mutants scaled below coverage one were refused: confirmed, independently re-implemented. The verifier shares no code with the source's checker and runs the same net-and-shrink method, so it is a second implementation and not a second method. The 6 October review of the certificate re-derived the 832-node net in exact arithmetic and found no defect. The source's own checker was also replayed here in full, the bundle's own driver over all 832 nodes with its assertions on, each returning the certificate's own record: confirmed, reproduced with the producer's code.
wand125 after Tokoharu and Levy, square-packing-bounds. Registration was requested in a comment of 6 October 2026 on jlevy/squares#366. The source says parts of the work were produced with AI assistance under human direction.
Significance, composition and next rung
- Significance
- The strongest verified lower bound on record at , by 0.004 above T-096, and the strongest reported. The certificate kind and checker of T-069 and later on a net twice as fine as T-096's, a parameter choice the same driver reads from the candidate; no new technique, at S3 as T-096, T-074 and T-045 are. The 6 October review confirmed the draft.
- Composition
- One primary certificate on its reported entry and its replay entry. The replay is sqverify-fast at all 832 directions of the net the retained candidate declares: one interval-certified method, replayed here by an independent implementation, C3, on the census route, whose per-certificate conditions for a declared net the soundness review of the declared-net change set and this certificate meets. Beside it, the bundle's own driver replayed the source's checker over all 832 nodes, the axis tables among them, each returning the shipped record: a complete reproduction with the producer's code, not a second method.
- Next rung
- V4 and C4 need two adversarial AI reviews of this result by distinct reviewers and a human oversight record. One is retained, the review of 6 October that read the certificate. A second machine method would be a method-distinct decision of rotated coverage; the complete replay of the source's own checker already stands beside the rung (E-n018-wand125-mixed-4704-source-replay).
- Novelty
- previously-published Present in an identified source
The case
Results on the case
17 results in the register on , oldest first, each with what it established and how it stands now.
2005 published T-007
for
V0 C1 lower bound incomplete on this case, superseded by T-102
Nagamochi · Nagamochi 2005 · source · register
2026-08-21 published T-016
for , by monotonicity from T-015
V3 C3 lower bound confirmed superseded by T-102
Massaccesi after Burns · Burns–Massaccesi n17 · packet · register
2026-08-31 established T-002
, by monotonicity from T-001
V3 C3 lower bound confirmed superseded by T-102
Levy after Bentz · register
2026-08-31 established T-003
The sixteen-point set's unavoidability ceiling lies in
V3 C3 method limit confirmed
Levy after Bentz · register
2026-09-04 established T-019
for
V3 C3 lower bound confirmed superseded by T-102
Levy after Burns, Massaccesi · register
2026-09-04 published T-085
Nagamochi 2005, Lemma 1 is false for every container with and
V3 C3 correction confirmed
Karakuş; chelokot · Karakuş 2026 · chelokot Nagamochi counterexample 2026 · packet · register
2026-09-18 established T-027
V3 C3 lower bound confirmed superseded by T-102
Levy after Burns, Massaccesi · register
2026-09-19 established T-028
V3 C3 lower bound confirmed superseded by T-102
Levy after Burns, Massaccesi · register
2026-09-19 established T-029
V3 C3 lower bound confirmed superseded by T-102
Levy after Burns, Massaccesi · register
2026-09-19 established T-030
V3 C3 lower bound confirmed superseded by T-102
Levy after Burns, Massaccesi · register
2026-09-27 published T-045
Rectangle-density lower bounds replayed at 15 counts in
V3 C3 lower bound confirmed superseded by T-102
wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 rectangle bounds 2026 · packet · packet · source · review · register
2026-09-27 published T-046
Rectangle-density lower bounds reported for 48 counts in
V0 C0 lower bound recorded superseded by T-102
wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 rectangle bounds 2026 · wand125 rectangle bounds 2026-09-28 · packet · packet · register
2026-09-29 published T-058
Rectangle-certificate ceiling
α·UB(n)proved for ..100;B·UB(n)on 64 grid rowsV3 C3 method limit confirmed
wand125 after Tokoharu, Daniel · wand125 tools 2026 · packet · register
2026-09-29 published T-083
for every nonsquare
V3 C3 lower bound confirmed on this case, superseded by T-102
Karakuş · Karakuş 2026 · source · register
2026-10-05 published T-096
Mixed rectangle-measure lower bound replayed at , on a net the certificate declares
V3 C3 lower bound confirmed superseded by T-102
wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds finer net 2026-10-05 · packet · source · review · register
2026-10-06 published T-099 this result
Mixed rectangle-measure lower bound verified at , on a finer declared net
V3 C3 lower bound confirmed superseded by T-102
wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds finer net 2026-10-06 · packet · source 1 · source 2 · review · register
2026-10-06 published T-102
Mixed rectangle-measure lower bound verified at , on the finest declared net yet
V3 C3 lower bound confirmed
wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds check2 2026-10-06 · packet · source · review · register
Links
- On this site
- Case record, · Frontier row, · T-099 in the results table
On GitHub, at main
- Register
- T-099 in
results.yaml, line 9913 - Evidence
E-n018-wand125-mixed-4704-report·E-n018-wand125-mixed-4704-sqverify-fast-replay·E-n018-wand125-mixed-4704-source-replay- Proofs and certificates
- certificate
candidate.json.gz· proofSOUNDNESS.md· auditreview-2026-10-06-wand125-finer-net-n18-n19.md· proofcontinuous-density-certificate.ja.md - Sources
- wand125 mixed bounds finer net 2026-10-06 (its own site, retained copy)
- Source packet
resources/web/wand125-mixed-bounds-finer-net-2026-10-06/README.md- Artifacts
18 artifacts and controls
resources/web/wand125-mixed-bounds-finer-net-2026-10-06/README.mdresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/audit.jsonresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/bundle.jsonresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/sample/nodes-000-831.jsonresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/full/compare.jsonresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/full/run.metaresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/full/processes.jsondevtools/audit_wand125_declared_net.pysqverify_fast/SOUNDNESS.mdbenchmarks/measure-verifier/census-mixed/census.jsonbenchmarks/measure-verifier/census-mixed/wand125-mixed-bounds-finer-net-2026-10-06/mixed_n18_L4704.jsonl.gzdevtools/sqverify_fast_census.pydocs/project/reviews/review-2026-10-06-wand125-finer-net-n18-n19.mddocs/project/reviews/review-2026-10-06-sqverify-fast-declared-net-soundness.mdbenchmarks/measure-verifier/census-mixed/wand125-mixed-bounds-finer-net-2026-10-06/mixed_n18_L4704.control.jsontests/test_sqverify_fast_census.pyresources/web/wand125-mixed-bounds-finer-net-2026-10-06/receipts/n18-L4704/control.jsontests/test_audit_wand125_declared_net.py- Case file
frontier/n-018.md(verified lower, verified upper, reported lower, reported upper)