T-225: Daniel's solved, regularized views at 204, 227, 229 and 260, each the smallest side reported there
V3 C3 Upper bound confirmed
Four complete rational source certificates report finite upper-bound improvements at the exact sides they state: , , and .
The four certificates and their duplicate-square and outside-container controls were decided here on 21 October 2026 by both maintained exact routes, and the frozen comparison rebuilt; no route here is the source's code, so the replay is independently re-implemented. The 21 October review reproduced it, decided each certificate again on a clean-room checker of its own, and found no blocking defect.
Each certificate is a display-regularized view, in Daniel's regularized record lists, of a packing already reported, solved to its exact side, and lies below that packing's certificate: by 1.39e-9 at 204 and 2.51e-11 at 260 below Couzo's #678 certificates (T-223), by 1.76e-11 at 227 below Couzo's #672 certificate (T-227), and by 1.91e-11 at 229 below Daniel's #674 update (T-199). Each side lies below the verified upper bound at the next count, so each bound is new.
Each certificate's JSON reports it VALID under the source's checkers and verified at 80 digits, prints S_cert, the side its certificate's header states, and S_exact, the 50-digit side of the solved packing it rounds up, and classes the view at level 2, same packing traversable without expansion, by a path test that samples angle moves and that the method log says is not a continuous proof. The commit says the six refreshed counts were certified and regularized, and of 229 that the polished side is 2e-11 below the posted one, the exact optimum of the same packing; each JSON says it is not a new bound. The checkers are byte-identical to the copies the n183 packet retains. Those statements are the author's; no source program ran here.
Credit the packings to their finders (at 227 the source's list names Couzo, whose #672 refines de Winter's packing): Couzo's at 204 (#678, T-223, which his source credits to Polkovskyi's construction) and 260 (#678, T-223, his arrangement from a search seeded with Daniel's exact-form certificate of de Winter's #668 packing); de Winter's at 227 (#668, T-196) as refined in Couzo's #672 report (T-227; who made the refinement the source does not say); and Daniel's own at 229 (#674, T-199, from Couzo's #672 packing, which refines de Winter's).
Daniel (https://github.com/evand/square-packing) refreshed each packing from his store, solved it to the exact side stated (at 229 after a polish), regularized it for display at that side and wrote the certificate. His credits say the repository's work was produced by Claude (Anthropic) under human direction.
Significance, composition and next rung
- Significance
- Smaller finite construction sides at 204, 227, 229 and 260, each the solved exact side of a packing already reported (Couzo's #678 at 204 and 260 and his #672 at 227, Daniel's #674 at 229), 1.76e-11 to 1.39e-9 below that packing's certificate and regularized for display: a citable detail of each case that moves no theorem, S2 as T-146 is. At 227 the drop of 1.71e-4 below T-196 is #672's (T-227), not this entry's. No lower bound or optimum. Drafted at intake, confirmed by review A of #716 and by the 21 October stage 4 review.
- Next rung
- None for the bound. V4 and C4 need a second accepted adversarial review by a distinct reviewer and a retained human oversight record; one AI review, of 21 October, is retained.
- Regularizations
- n = 204: a regularization of T-223’s packing by Daniel (conservative; solved to its side; the regularizer changed no angle, as its source reports; identity: the source’s claim; nearest centres one to one; 58 squares moved, at most 0.442; turns up to 0.159°).
n = 227: a regularization of T-227’s packing by Daniel (conservative; solved to its side; the regularizer changed no angle, as its source reports; identity: the source’s claim; nearest centres one to one; 16 squares moved, at most 0.168; turns up to 2.542°).
n = 229: a regularization of T-199’s packing by Daniel (conservative; solved to its side; the regularizer changed no angle, as its source reports; identity: the source’s claim; nearest centres not one to one).
n = 260: a regularization of T-223’s packing by Daniel (conservative; solved to its side; the regularizer changed no angle, as its source reports; identity: the source’s claim; nearest centres not one to one). - Regularized drawings
- n = 204: a regularization of T-225’s packing by Levy (regularize_axis_components/2; at its own side; identity: measured here; nearest centres one to one; 0 squares moved, at most 1.57542e-17; no square turned).
n = 227: a regularization of T-225’s packing by Levy (Daniel's search/regularize (MIT), evand/square-packing@675a5ea, conservative, coincide, through devtools.regularize_evand; the project’s modifications: same-side exact re-solve (devtools.regularize_same_side); at its own side; 1 free angle moved; identity: measured here; nearest centres one to one; 1 square moved, at most 0.0509347; no square turned).
n = 229: a regularization of T-225’s packing by Levy (regularize_grid_slack/1: Daniel's coincidence placement (evand/square-packing search/regularize reg.coincidences and reg.place, MIT), ported to start from the witness's exact frame and to keep its contacts, then the same-side exact re-solve, through devtools.regularize_grid_slack; the project’s modifications: port of his coincidence placement (regularize_grid_slack/1) rather than his code, same-side exact re-solve (devtools.regularize_same_side); at its own side; identity: measured here; nearest centres one to one; 58 squares moved, at most 0.0381281; no square turned).
n = 260: a regularization of T-225’s packing by Levy (regularize_axis_components/2; at its own side; identity: measured here; nearest centres one to one; 0 squares moved, at most 1.251e-19; no square turned). - Novelty
- previously-published Present in an identified source
The cases
Proven
- exact
Citation record n-204
lowerKarakuş 2026, arXiv corrects Nagamochi 2005 (confirmed T-083)
upperCouzo & Daniel, GitHub (confirmed T-225)
Open
- optimality
The case record
As published
Proven
- exact
Citation record n-227
lowerKarakuş 2026, arXiv corrects Nagamochi 2005 (confirmed T-083)
upperde Winter et al., GitHub (confirmed T-225)
Open
- optimality
The case record
As published
Proven
- exact
Citation record n-229
lowerKarakuş 2026, arXiv corrects Nagamochi 2005 (confirmed T-083)
upperDaniel 2026, GitHub (confirmed T-225)
Open
- optimality
The case record
Proven
- exact
Citation record n-260
lowerKarakuş 2026, arXiv corrects Nagamochi 2005 (confirmed T-083)
upperCouzo & Daniel, GitHub (confirmed T-225)
Open
- optimality
The case record
Results on these cases
19 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 these cases, superseded by T-083 and T-180 (reported)
2026-09-04 published T-085 ·
Nagamochi 2005, Lemma 1 is false for every container with and
V3 C3 Correction confirmed
Karakuş; Vlasenko · Karakuş 2026 · chelokot Nagamochi counterexample 2026 · packet · register
2026-09-29 published T-083 ·
for every nonsquare
V3 C3 Lower bound confirmed
Karakuş · Karakuş 2026 · source · register
2026-10-05 published T-101 ·
Exact certificates of 77 catalogue packings:
s(n) ≤ S',1.2e-16to9.8e-15above each sideV3 C3 Upper bound confirmed on these cases, superseded by T-225
Daniel after Couzo, de Winter, Ellsworth, Levy · evand exact optima 2026-10-05 · packet · register
2026-10-12 established T-155 ·
Exact regularized sides at 59 counts,
5.4e-20to9.9e-15below the ceilings they replaceV3 C3 Upper bound confirmed on these cases, superseded by T-225
2026-10-12 published T-162 ·
New packings of 129, 204 and 303 squares, a cut-out and two compositions, each certified exactly
V3 C3 Upper bound confirmed superseded by T-225
Ostashev after Nakajima, Chaoweeraprasit, Daniel, Xu, Levy · Ostashev compositions 2026-10-12 · packet · register
2026-10-13 published T-174 ·
Tighter certificates at 68 counts from PingYou Ltd, of others' packings and its own
V3 C3 Upper bound confirmed on these cases, superseded by T-225
PingYou Ltd after Friedman, Ellsworth, Daniel, Xu, Barnett, Couzo, Ostashev, Chaoweeraprasit, Gupta, Fang, Polkovskyi, Levy · PingYou PR 574 certificates 2026-10-13 · packet · register
2026-10-13 published T-180 ·
Closed-form lower bound for every non-square , reported
V0 C1 Lower bound reviewed
Hosono · wand125 closed form 2026-10-14 · packet · packet · register
2026-10-14 published T-186 ·
Exact certificates at twelve counts from Polkovskyi, tightening the smallest reported there
V3 C3 Upper bound confirmed on these cases, superseded by T-225
Polkovskyi after Ostashev, Couzo, PingYou Ltd, Levy · Mishapolk KKT refinements 2026-10-14 · packet · register
2026-10-16 published T-193 ·
Exact algebraic sides at sixteen counts from Daniel, of packings the record credits
V3 C3 Upper bound confirmed on these cases, superseded by T-225
Daniel after Xu, Chaoweeraprasit, Ostashev, Couzo, PingYou Ltd, Gupta, Polkovskyi, Levy · Daniel exact current records 2026-10-16 · packet · register
2026-10-17 published T-196 ·
de Winter reports three smaller rational upper bounds at 227, 229 and 260
V3 C3 Upper bound confirmed superseded by T-225
de Winter after Levy · de Winter upper bounds 2026-10-17 · packet · register
2026-10-17 published T-198 ·
Daniel's opening n229 dilation certificate, after Couzo and de Winter
V3 C3 Upper bound confirmed superseded by T-225
Daniel after Couzo, de Winter, Levy · Daniel n229 dilation 2026-10-17 · packet · register
2026-10-17 published T-226 ·
Couzo's 204 of #670, below Polkovskyi's T-186, since superseded by his own #675 and #678
V0 C0 Upper bound recorded superseded by T-225
Couzo after Polkovskyi, Daniel, Levy · Couzo issue 670 2026-10-17 · packet · packet · register
2026-10-17 published T-227 ·
Couzo's refinements of de Winter's 227 and 229, below T-196 at both
V0 C0 Upper bound recorded superseded by T-225
Couzo after de Winter, Daniel, Levy · Couzo issue 672 2026-10-17 · packet · packet · register
2026-10-18 published T-199 ·
Daniel's smaller n229 update, replacing the opening certificate
V3 C3 Upper bound confirmed superseded by T-225
Daniel after Couzo, de Winter, Levy · Daniel n229 dilation update 2026-10-18 · packet · register
2026-10-18 published T-223 ·
Couzo's smaller packings at 204 and 260, the two in the corpus of issue 678's 85 bounds
V3 C3 Upper bound confirmed superseded by T-225
Couzo after de Winter, Polkovskyi, Daniel, Fang, PingYou Ltd, Levy · Couzo issue 678 2026-10-18 · packet · register
2026-10-18 published T-228 ·
Couzo's 204 of #675, below his #670, since superseded by his #678
V0 C0 Upper bound recorded superseded by T-225
Couzo after Polkovskyi, Daniel, Levy · Couzo issue 675 2026-10-18 · packet · packet · register
2026-10-20 published T-225 this result ·
Daniel's solved, regularized views at 204, 227, 229 and 260, each the smallest side reported there
V3 C3 Upper bound confirmed
Daniel after Couzo, de Winter, Polkovskyi, Levy · Daniel regularized lists 2026-10-20 · packet · register
2026-10-22 published T-229 ·
Polkovskyi's re-solves of the house packings at 105 and 204, below T-174 and T-225
V0 C0 Upper bound recorded
Polkovskyi after Couzo, Muglich, Daniel, Xu, PingYou Ltd, Levy · Mishapolk issue 719 2026-10-22 · packet · register
Links
- On this site
- Case record, · Frontier row, · Case record, · Frontier row, · Case record, · Frontier row, · Case record, · Frontier row, · T-225 in the results table
On GitHub, at main
- Register
- T-225 in
results.yaml, line 30773 - Evidence
E-evand-regularized-1020-certificate-report·E-evand-regularized-1020-exact-feasibility·E-evand-regularized-1020-review-exact-feasibility- Proofs and certificates
- certificate
certs - Sources
- Daniel regularized lists 2026-10-20 (its own site, retained copy)
- Source packet
resources/web/evand-regularized-2026-10-20/README.md- Artifacts
15 artifacts and controls
resources/web/evand-regularized-2026-10-20/README.mdresources/web/evand-regularized-2026-10-20/acquisition/claims.jsonresources/web/evand-regularized-2026-10-20/source/search/regularize/lists/certs/n-204.cert.gzresources/web/evand-regularized-2026-10-20/source/search/regularize/lists/certs/n-227.cert.gzresources/web/evand-regularized-2026-10-20/source/search/regularize/lists/certs/n-229.cert.gzresources/web/evand-regularized-2026-10-20/source/search/regularize/lists/certs/n-260.cert.gzresources/web/evand-regularized-2026-10-20/receipts/exact-certification.json.xzresources/web/evand-regularized-2026-10-20/measure/identity.jsoncampaign/issue-intake/upper-bounds-20261021/README.mddevtools/upper_bound_reports.pydocs/project/reviews/review-2026-10-21-evand-regularized-views.mdresources/web/evand-regularized-2026-10-20/review/review-2026-10-21/README.mdtests/test_upper_bound_reports.pytests/test_upper_bound_reports_regularized_1020.pyresources/web/evand-regularized-2026-10-20/receipts/exact-certification.json.xz- Case file
frontier/n-204.md(verified lower, verified upper, reported lower, reported upper) ·frontier/n-227.md(verified lower, verified upper, reported lower, reported upper) ·frontier/n-229.md(verified lower, verified upper, reported lower, reported upper) ·frontier/n-260.md(verified lower, verified upper, reported lower, reported upper)