T-136: Seventeen exact rational packings from SQUISH's third request
V3 C3 upper bound confirmed
Seventeen complete rational source certificates by Nate Chaoweeraprasit, using SQUISH, reported on jlevy/squares#481, prove finite upper bounds at the exact sides they state: , , , , , , , , , , , , , , , and .
Each certificate gives a rational side and, for each unit square, a rational centre and the tangent of its half-angle, in SQUISH's JSON; each side is the exact fraction the source's summary.csv prints, and the issue's 15-digit displays are not roundings of it. The author reports that SQUISH's exact Fraction checker accepts all seventeen and David Ellsworth's check_packing.py each 50-digit export, and that each certificate was drawn from a 60-digit contact solution with clearance 1e-32, about 1e-14 at 263 and 292.
At every count squares touch the closed box, a least wall clearance of exactly 0, which the record's closed-box convention admits; no two squares meet, and the bound also holds if is read as an open-box infimum.
All 51 retained jobs, the seventeen positives with their duplicate-square and outside-container controls, were decided again here on 10 October 2026 by both maintained exact routes, from exact facts derived from the pinned certificates, and equal their retained rows. A third exact route, half-extent containment and exact intersection area, decided the seventeen with six controls each and found each fact to be the packing its pinned upstream file states. No route here is the source's code, so the replay is independently re-implemented. The 10 October review found no blocking defect.
Each side is below the ceiling its case holds, and below every other report pending at its count except at 209, 237, 270 and 305, where Francisco Couzo's later certificates of issue 488 (T-140) are smaller, and at 153, 236, 263, 269, 292, 302 and 303, where Evan Daniel's later regularized certificates (T-146) are smaller; the case records are unchanged until a house is adopted, so each is pending adoption.
Credit Nate Chaoweeraprasit (https://github.com/itsnaka/squish-certs), using SQUISH and its Mondrian composition method, after Francisco Couzo, Ryan Xu, Frits Göbel, Thomas Schadt, David Ellsworth and Károly Hajba, whose packings supplied pieces, as the issue's credit line names them. Per count, the issue lists the pieces: the Kingbird catalogue's packing of 5 and former records at 11, 50, 152, 202 and 241, Francisco Couzo's packings of 182 and 180, Ryan Xu's of 123, 129 and 175, and SQUISH's own earlier packings. The source states that the solver, its verification and the issue were written with Claude Opus 5.5 under the author's direction.
Significance, composition and next rung
- Significance
- Smaller finite construction sides at , 153, 154, 207, 209, 232, 236, 237, 259, 263, 269, 270, 292, 302, 303, 305 and 307, 1.68e-04 to 1.12e-02 below the case ceilings; no lower bound or optimum.
- Next rung
- V4 and C4 need a retained human oversight record: two accepted adversarial reviews by distinct AI reviewers are retained, the 10 October review and the 11 October final review (docs/project/reviews/review-2026-10-11-final-upper-bounds.md). Separately, once jlevy/squares#403 lands and private-worker custody is on file (RI-5), adopt this entry as the house at 131, 154, 207, 232, 259 and 307, the six counts where it is the smallest, with each earlier house kept as history. At 153, 236, 263, 269, 292, 302 and 303 the house recommendation goes to T-146, whose 11 October review accepted it.
- Novelty
- previously-published Present in an identified source
The cases
This result concerns 17 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.
| n | Proved lower | Best known | Gap | Status | Records |
|---|---|---|---|---|---|
| 131 | 11.465856 | 11.951151 | 0.48529394… | open= | frontier n-131.md |
| 153 | 12.384864 | 12.879680 | 0.49481504… | frontier n-153.md | |
| 154 | 12.426860 | 12.926563 | 0.49970180… | frontier n-154.md | |
| 207 | 14.401438 | 14.887993 | 0.48655348… | frontier n-207.md | |
| 209 | 14.473188 | 14.949618 | 0.47642933… | frontier n-209.md | |
| 232 | 15.239402 | 15.778175 | 0.53877162… | frontier n-232.md | |
| 236 | 15.374474 | 15.867801 | 0.49332605… | frontier n-236.md | |
| 237 | 15.408051 | 15.903677 | 0.49562471… | frontier n-237.md | |
| 259 | 16.096473 | 16.602569 | 0.50609453… | open≈ | frontier n-259.md |
| 263 | 16.224185 | 16.740420 | 0.51623448… | open= | frontier n-263.md |
| 269 | 16.413830 | 16.905968 | 0.49213659… | open≈ | frontier n-269.md |
| 270 | 16.445218 | 16.937808 | 0.49258850… | open= | frontier n-270.md |
| 292 | 17.090660 | 17.597250 | 0.50658936… | frontier n-292.md | |
| 302 | 17.389345 | 17.881307 | 0.49196046… | frontier n-302.md | |
| 303 | 17.418924 | 17.920313 | 0.50138805… | frontier n-303.md | |
| 305 | 17.477926 | 17.952960 | 0.47503261… | open≈ | frontier n-305.md |
| 307 | 17.536725 | 17.981031 | 0.44430551… | frontier n-307.md |
Results on these cases
23 results in the register on these cases, oldest first
2005 published T-007 · 17 of these cases
for
lower bound incomplete
Nagamochi · Nagamochi 2005 · source · register
2026-09-04 published T-085 · 17 of these cases
Nagamochi 2005, Lemma 1 is false for every container with and
correction confirmed
Karakuş; chelokot · Karakuş 2026 · chelokot Nagamochi counterexample 2026 · packet · register
2026-09-27 published T-056 · 15 of these cases
Smaller packings for 49 counts from to , each certified two independent ways
upper bound confirmed superseded by T-098, T-113, T-116, T-117, T-119, T-125 and T-127
Couzo · franciscouzo square-packing 2026-09-27 · packet · register
2026-09-29 published T-083 · 17 of these cases
for every nonsquare
lower bound confirmed
Karakuş · Karakuş 2026 · source · register
2026-10-03 published T-092 · cases 209, 263, 303
Smaller packings again at seven counts from to , each certified two independent ways
upper bound confirmed superseded by T-113, T-116 and T-127
Couzo · franciscouzo square-packing 2026-10-03 · packet · register
2026-10-05 published T-098 · 14 of these cases
Exact optima of 48 known-best packings:
s(n) ≤ S',3.5e-13to5.0e-11below each printed sideupper bound confirmed
Daniel after Couzo, de Winter, Ellsworth, Levy · evand exact optima 2026-10-05 · packet · register
2026-10-05 published T-101 · cases 153, 232
Exact certificates of 77 catalogue packings:
s(n) ≤ S',1.2e-16to9.8e-15above each sideupper bound confirmed
Daniel after Couzo, de Winter, Ellsworth, Levy · evand exact optima 2026-10-05 · packet · register
2026-10-07 published T-113 · cases 154, 209, 303
at ten counts, to 303, from new SQUISH rational packings
upper bound confirmed
Chaoweeraprasit after Ellsworth · SQUISH ten packings 2026-10-07 · packet · register
2026-10-07 published T-114 · case 153
, from a SQUISH rational packing
upper bound confirmed superseded by T-127
Chaoweeraprasit after Ellsworth · SQUISH n153 2026-10-07 · packet · packet · register
2026-10-07 published T-115 · cases 154, 237, 263
at twelve counts, from the SQUISH update’s new and smaller rational packings
upper bound confirmed on these cases, superseded by T-116 and T-127
Chaoweeraprasit after Couzo and Ellsworth · SQUISH update 2026-10-07 · packet · register
2026-10-07 published T-116 · cases 207, 236, 263, 302
at nine counts, from the second SQUISH update’s new rational packings
upper bound confirmed
Chaoweeraprasit after Ellsworth, Couzo and SQUISH · SQUISH second update 2026-10-07 · packet · register
2026-10-07 published T-117 · case 292
Exact rational ceiling refinements at , 292
upper bound confirmed
Rehwaldt after Couzo and earlier contributors · Rehwaldt Couzo refinements 2026-10-07 · packet · register
2026-10-07 published T-119 · case 270
Three exact feasible upper bounds at n=266,270,272 from new source arrangements
upper bound confirmed
Daniel after Levy, Ellsworth, Couzo, Stead · Daniel new arrangements 2026-10-07 · packet · register
2026-10-07 published T-129 · case 292
Three dated Daniel certificate reports with historical source custody
upper bound recorded superseded by T-117
Daniel after Couzo, Levy · Daniel dated certificates 105 and 130 2026-10-07 · Daniel dated certificate 292 2026-10-07 · packet · packet · packet · register
2026-10-08 published T-125 · cases 131, 153, 236, 263
Complete rational construction reports at 25 counts
upper bound confirmed
ry-xu · ry-xu square packing 2026 · packet · register
2026-10-08 published T-127 · 6 of these cases
Fourteen rational refinements, seventeen complete source cases
upper bound confirmed
Gupta after Chaoweeraprasit, Daniel · Gupta rational refinements 2026-10-08 · packet · register
2026-10-08 published T-128 · case 131
Eight complete rational refinements from Francisco Couzo
upper bound confirmed
Couzo after Xu, Chaoweeraprasit, Gupta, Ellsworth, Daniel, Levy · Couzo exact refinements 2026-10-08 · packet · register
2026-10-08 published T-130 · case 270
Five follow-up rational refinements from Francisco Couzo
upper bound confirmed
Couzo after Xu, Daniel, Ellsworth, Levy · Couzo follow-up refinements 2026-10-08 · packet · register
2026-10-09 published T-134 · cases 237, 263, 270, 303
Six exact rational certificates from Francisco Couzo
upper bound confirmed
Couzo after Mishapolk, Chaoweeraprasit, Gupta, Xu, Daniel, Ellsworth, Levy · Couzo exact certificates 2026-10-09 · packet · register
2026-10-09 published T-136 this result · 17 of these cases
Seventeen exact rational packings from SQUISH's third request
upper bound confirmed
Chaoweeraprasit after Couzo, Xu, Goebel, Schadt, Ellsworth, Hajba, Levy · SQUISH third request 2026-10-09 · packet · register
2026-10-09 published T-138 · cases 131, 270, 302, 303
Exact witnesses at Mishapolk's printed ceilings, the smallest known at 103 and 258 when registered
upper bound confirmed
Mishapolk after Stenlund, Friedman, Ellsworth, Chaoweeraprasit, Couzo, Xu, Levy · Mishapolk decimal poses 2026-10-09 · packet · register
2026-10-10 published T-140 · cases 209, 237, 270, 305
Six more exact rational certificates from Francisco Couzo
upper bound confirmed
Couzo after Chaoweeraprasit, Mishapolk, Xu, Daniel, Ellsworth, Levy · Couzo certificates 2026-10-10 · packet · register
2026-10-10 published T-146 · 7 of these cases
Exact rational certificates at fifteen counts from Evan Daniel's regularized record lists
upper bound confirmed
Daniel after Xu, Chaoweeraprasit, Mishapolk, Levy · Daniel regularized lists 2026-10-10 · packet · register
Links
- On this site
- The frontier survey · T-136 in the results table
On GitHub, at main
- Register
- T-136 in
results.yaml, line 14124 - Evidence
E-squish-481-certificate-report·E-squish-481-exact-feasibility- Proofs and certificates
- certificate
facts - Sources
- SQUISH third request 2026-10-09
- Source packet
resources/web/squish-481-third-request-2026-10-09/README.md- Artifacts
41 artifacts and controls in 7 directories. Complete artifact list in the result entry. docs/project/reviews packing/devtools packing/resources/web/squish-481-third-request-2026-10-09 packing/resources/web/squish-481-third-request-2026-10-09/acquisition packing/resources/web/squish-481-third-request-2026-10-09/facts packing/resources/web/squish-481-third-request-2026-10-09/receipts packing/tests
- Case file
- each case’s file is linked from its row above