T-069: Mixed rectangle-measure lower bounds replayed at n=37,65,66,90,92

V3 C3 lower bound confirmed

2026-10-01 published · wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · 5 cases, n=37 to 92

Five rectangle densities of wand125/square-packing-bounds, checked at coverage one and published between 29 September and 1 October 2026, prove s(37)≥161/25 = 6.44, s(65)≥167/20 = 8.35, s(66)≥421/50 = 8.42, s(90)≥48/5 = 9.6 and s(92)≥969/100 = 9.69.

Each certificate is a density of uniform rectangles with no point mass, of total mass n - 1/100000, at core side 9977/10000 on 201 net half-angles of step 83/40000: 350 rectangles at n=37, 787 at n=65, 631 at n=66, 762 at n=90 and 832 at n=92. Each is accepted at every oblique net angle by code/mixed_rotated_verify.cpp, the research copy of Tokoharu's verify.cpp that the source's s(50) certificate uses (T-048), which accepts coverage at least 1 where Tokoharu's requires 10001/10000, and at angle zero by exact integer tables. The least oblique lower bounds run from 1.000000000042 at n=90 to 1.0000000054 at n=37.

At n=65 the value exceeds Green's reported 8.2899656, which is 2 sqrt(2) + 71/13, and at n=92 Nagamochi's 1 + sqrt(75) = 9.6602540. At n=37, 66 and 90 it exceeds the rectangle certificates of the same source that this record reports.

Each certificate passed a complete replay here on 2 October 2026 of the source's unchanged checker and per-angle functions on its pinned tarball: all 201 directions, each returning the certificate's own record. The replays run the source's own algorithm and are not an independent decision of coverage.

wand125 after Tokoharu and Levy, square-packing-bounds. Registration was requested in jlevy/squares#282. The source says parts of the work were produced with AI assistance under human direction.

Significance, composition and next rung
Significance
Raised the verified lower bound at five counts, by 0.03 to 0.34 over Nagamochi's closed form, two of them past Green's and Nagamochi's reported values, by the certificate kind of T-048. Further sizes from one generator at S3; the 2 October review of these certificates confirmed S3. Since Karakuş's finding (T-085, merged 2026-10-03) the closed form is itself a reported bound, and the margins over the verified floor it left behind, Karakuş's general bound, are larger.
Composition
One claim per count, each on its own certificate, its own reported entry and its own replay entry. Each replay runs the source's C++ checker unchanged: one interval-certified method, replayed here, C3. Coverage is decided by that checker alone; the axis tables are a second implementation for one direction and not a second method.
Next rung
V4 and C4 need two adversarial AI reviews by distinct reviewers and a human oversight record; one adversarial review is retained. A second machine method would be a method-distinct decision of rotated coverage; the replays here run the source's own checker. The checker's controls were made on the n=37 certificate.
Novelty
previously-published Present in an identified source

The cases

This result concerns 5 cases, too many to draw one by one. Each is listed with the film’s bounds, the proved lower bound and the best known side, and links to its case record, where its packing and number line are drawn.

nProved lowerBest knownGapStatusRecords
376.4400006.5986200.15861960…open=frontier n-037.md
658.3500008.5355340.18553390…frontier n-065.md
668.4300008.6568550.22685424…frontier n-066.md
909.730000100.27frontier n-090.md
929.7700000.23frontier n-092.md

Results on these cases

14 results in the register on these cases, oldest first
  1. 2005 published T-007 · 5 of these cases

    s(n)≥min(⌈n⌉,n−2⌊n⌋+1+1) for 4≤n≤324

    lower bound incomplete on these cases, superseded by T-069, T-082, T-091 and T-097

    Nagamochi · Nagamochi 2005 · source · register

  2. 2018 published T-087 · case 37

    s(37)≥53/2+22−1 and s(61)≥73/2+22−1, by optimal piercing

    lower bound reviewed superseded by T-069

    Bašić, Slivková · Basic-Slivkova 2018 · source · register

  3. 2026-09-04 published T-085 · 5 of these cases

    Nagamochi 2005, Lemma 1 is false for every container with a>3 and b>2

    correction confirmed

    Karakuş; chelokot · Karakuş 2026 · chelokot Nagamochi counterexample 2026 · packet · register

  4. 2026-09-27 published T-046 · cases 37, 66, 90

    Rectangle-density lower bounds reported for 48 counts in n=18…95

    lower bound recorded superseded by T-069, T-091 and T-097

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 rectangle bounds 2026 · wand125 rectangle bounds 2026-09-28 · packet · packet · register

  5. 2026-09-29 published T-058 · 5 of these cases

    Rectangle-certificate ceiling α·UB(n) proved for n=1..100; B·UB(n) on 64 grid rows

    method limit confirmed

    wand125 after Tokoharu, Daniel · wand125 tools 2026 · packet · register

  6. 2026-09-29 published T-083 · 5 of these cases

    s(n)≥1/2+n−⌊n⌋+1/4 for every nonsquare 8≤n≤324

    lower bound confirmed on these cases, superseded by T-069, T-082, T-091 and T-097

    Karakuş · Karakuş 2026 · source · register

  7. 2026-10-01 published T-068 · cases 66, 90

    Rectangle-density lower bounds verified at 34 counts in n=19…95

    lower bound confirmed on these cases, superseded by T-091 and T-097

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 rectangle bounds 2026-10-01 · packet · source · review · register

  8. 2026-10-01 published T-069 this result · 5 of these cases

    Mixed rectangle-measure lower bounds replayed at n=37,65,66,90,92

    lower bound confirmed

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds 2026-10-01 · packet · source · review · register

  9. 2026-10-02 published T-075 · case 92

    Mixed rectangle-measure lower bounds replayed at nine counts in n=83…96

    lower bound confirmed on these cases, superseded by T-082

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds afternoon 2026-10-02 · packet · source 1 · source 2 · review · register

  10. 2026-10-03 published T-082 · cases 90, 92

    Mixed rectangle-measure lower bounds verified at 22 counts in n=51…96

    lower bound confirmed

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds 2026-10-03 · packet · packet · source · review · register

  11. 2026-10-04 published T-091 · cases 90, 92

    Mixed rectangle-measure lower bounds verified at 17 counts in n=53…95

    lower bound confirmed

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds evening 2026-10-04 · packet · source · review · register

  12. 2026-10-05 published T-097 · case 66

    Mixed rectangle-measure lower bound verified at n=66

    lower bound confirmed

    wand125 after Tokoharu, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 mixed bounds finer net 2026-10-05 · packet · source · review · register

  13. 2026-10-05 published T-101 · case 37

    Exact certificates of 77 catalogue packings: s(n) ≤ S', 1.2e-16 to 9.8e-15 above each side

    upper bound confirmed

    Daniel after Couzo, de Winter, Ellsworth, Levy · evand exact optima 2026-10-05 · packet · register

  14. 2026-10-07 published T-124 · cases 90, 92

    Reported non-strict local minima for 178 source configurations

    restricted optimality recorded

    Daniel after Couzo · Daniel exact and local reports 2026 · packet · register