T-064: s(k2−3)=k for every integer k from 6 up; k=6…18 are the cases held here

V3 C3 optimality confirmed

2026-09-30 published · Daniel after Burns, Massaccesi · 13 cases, n=33 to 321

Evan Daniel's theorem s(k^2 - 3) = k for every integer k >= 6, dated 29 September 2026 by the source and public in its repository on 30 September: the lower half by one family of periodic measures, the upper half by the k x k grid.

This entry's scope is the projection of that theorem onto the cases this record holds, n <= 324, which is k = 6 to 18: s(33)=6, s(46)=7, s(61)=8, s(78)=9, s(97)=10, s(118)=11, s(141)=12, s(166)=13, s(193)=14, s(222)=15, s(253)=16, s(286)=17 and s(321)=18. The reported theorem does not end at k = 18.

For each k the measure on [0,k]^2 is a corner module in each corner, a profile of period one along each wall and Lebesgue measure on the middle square, of total mass k^2 - 4D with D = 423621306389/500000000000, so that 4D exceeds 3. The source states that every closed unit square in [0,k]^2 has mass at least one, and reduces that, for every k >= 6, to one finite statement it calls Valid7: every closed unit square in [0,7]^2 has mass at least one under the k = 7 measure.

The source's Lean development takes Valid7 as a hypothesis and, the source reports, kernel-checks that it implies the theorem for every k >= 6; it does not prove Valid7. Valid7 is the claim of the source's exact-rational Python checker, qx2_zm.py, which the source reports accepting all 9,800 root boxes in 32,079 leaves, with the axis-parallel poses decided by a separate exact enumeration; it reports six adversarial reviews of the certificate by AI agents and none by outside mathematicians.

On 2 October 2026 wand125 published a second, separately written exact-rational checker of Valid7 on the same cover, which reports all 156,800 root boxes of the unreduced pose space certified in 9,640,060 leaves, about 626 core-hours, and says Daniel's checker and lemma write-ups were not read. The two share the statement, the cover and its format.

Here both parts of the lower half were rebuilt. Daniel's checker was replayed in full on the retained cover on 2 and 3 October 2026, in two shards: all 9,800 root boxes and 32,079 leaves, none uncertified, each root's leaves equal to the published run's, which discharges Valid7 for this cover. The Lean reduction was built from retained bytes with the pinned toolchain, and bentz_of_valid7 depends only on the standard axioms. Together they prove the theorem here, for every k >= 6.

wand125's second checker was reviewed on 2 October and found sound but for one defect in its exact positivity test (D-1), which cannot make a true Valid7 fail. It was replayed here in full on 2 and 3 October with that test's accepting case made a refusal, in fourteen shards: all 156,800 root boxes certified in 9,808,968 leaves, none uncertified, and each root the source ran under its published code with the published leaves. So Valid7 is decided here by two separately written exact checkers, Daniel's reproduced with the producer's code and wand125's independently re-implemented.

So s(97)=10, s(118)=11, s(141)=12, s(166)=13, s(193)=14, s(222)=15, s(253)=16, s(286)=17 and s(321)=18 are proved here, nine cases closed. s(33)=6 and s(46)=7 were proved already on Bentz's proofs, s(61)=8 on Daniel's s(60) cover (T-063), and s(78)=9 on wand125's s(77) cover (T-067); this family proves each again by another route.

Evan Daniel, evand/square-packing, building on Burns's and Massaccesi's method. The source's CREDITS.md says the work was produced by Claude (Anthropic) in a single session under human direction.

Significance, composition and next rung
Significance
Scored as a claim: a bound family, which would settle eleven open cases of this record and every later k if the finite premise and its reduction pass replay and review here. S4 by the anchor "a reusable technique, bound family"; the score gates nothing.
Composition
Compound, and the minimum is set by the lower half. The upper half is the k x k grid, E-basic-grid-upper, replayed exactly here. The lower half is two parts in series: the finite premise Valid7 for the k = 7 cover, decided by the full replay of Daniel's exact checker (E-k2m3-evand-valid7-qx2-replay, exact-algebraic, same-implementation), and the reduction from Valid7 to every k >= 6, kernel-checked here (E-k2m3-evand-bentz-lean-build, proof-assistant-checked, with its axiom receipt). Each is V3 and C3, so the result is.

Valid7 has a second replayed checker, wand125's separately written one, replayed here in full with D-1 guarded (E-k2m3-wand125-valid7-independent, exact-algebraic, independent-implementation). It is the same method as Daniel's, so it adds no distinct method and moves no rung. No human formalization review is retained, so the Lean build does not reach rung 5. The scope lists the cases this record holds, since a scope is a set of cases; the theorem's own domain is every k >= 6, and a scope that can say so is think-kqi1.
Next rung
V4 and C4 need two adversarial AI reviews by distinct reviewers of the claim and a human oversight record; the one retained review read the second checker's method and the reduction's statement. Valid7's two replayed checkers are both exact-algebraic; a checker of another kind, interval-certified or a Lean proof of Valid7, would add a method beside the rung. Rung 5 needs human formalization reviews of the Lean statement and a Lean proof of Valid7 itself.

The source has begun that proof: by 4 October its Lean reduces Valid7 to the tilted part ValidTilt7 (bentz_of_validTilt7, with the D4 reduction and the axis face proved) and kernel-checks the 689 LEB and 374 CAP leaves of the run's 32,079 with Lemmas U and K, as reported and not built here; the tree that joins the leaves and the 26,829 PIECE and EXACT leaves remain. think-kqi1 tracks a scope that can state an infinite family.

The source also reports an interval-certified checker: its zmx2 with area density decides Valid7 by a sweep of the whole pose space, about 400 CPU-seconds at the source, retained with its run records in the 4 October evand packet and not replayed here (E-k2m3-evand-family-report, think-83zc). The source still waits for a second reader of its newest lemmas.
Novelty
previously-published Present in an identified source

The cases

This result concerns 13 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.

Results on these cases

13 results in the register on these cases, oldest first
  1. 2005 published T-007 · 13 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-008, T-063, T-064 and T-067

    Nagamochi · Nagamochi 2005 · source · register

  2. 2010-09-13 published T-004 · case 46

    Bentz 2010, Theorem 8 (s(46)≥7) is correct as printed, machine-audited in full

    audit confirmed

    Bentz · Bentz 2010 · source · register

  3. 2010-09-13 published T-008 · case 46

    s(46)=7

    optimality confirmed

    Bentz · Bentz 2010 · source · register

  4. 2018 published T-087 · case 61

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

    lower bound reviewed superseded by T-063

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

  5. 2026-09-04 published T-085 · 13 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

  6. 2026-09-27 published T-045 · cases 61, 78

    Rectangle-density lower bounds replayed at 15 counts in n=18…78

    lower bound confirmed superseded by T-063, T-064 and T-067

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

  7. 2026-09-27 published T-046 · cases 61, 78

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

    lower bound recorded superseded by T-063, T-064 and T-067

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

  8. 2026-09-28 published T-063 · case 61

    s(61)=8, by monotonicity from T-062

    optimality confirmed

    Daniel after Burns, Massaccesi · evand square-packing 2026-10-01 · packet · packet · packet · source 1 · source 2 · review 1 · review 2 · register

  9. 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

  10. 2026-09-29 published T-083 · 13 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-008, T-063, T-064 and T-067

    Karakuş · Karakuş 2026 · source · register

  11. 2026-09-30 published T-064 this result · 13 of these cases

    s(k2−3)=k for every integer k from 6 up; k=6…18 are the cases held here

    optimality confirmed

    Daniel after Burns, Massaccesi · evand square-packing 2026-10-01 · packet · packet · packet · packet · source 1 · source 2 · review 1 · review 2 · register

  12. 2026-10-01 published T-067 · case 78

    s(77)=9, by a mixed cover extended from Daniel's s(60) cover

    optimality confirmed

    wand125 after Daniel, Levy, Stromquist, Nagamochi, Burns, Massaccesi · wand125 exact covers 2026-10-01 · packet · source · review · register

  13. 2026-10-07 published T-124 · 13 of these cases

    Reported non-strict local minima for 178 source configurations

    restricted optimality recorded

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