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Subject and independence

The reviewer is an independent examiner working in a fresh context from the commissioned assignment alone. The reviewer took no part in writing the page, its sibling reconstruction pages or the folder's evidence, consulted no other review, ran no web search, and read nothing under the folder's evidence/ directory.

Frozen subject: path wiki/research/erdos_354/yu_chen_theorem_5_1_reconstruction.md as it stood at 2026-09-28T05:03:27Z, read in full as of that time.

Artifact: the seventeen-page PDF held by the library source card Yu and Chen (2026) (the folder-name PDF, 138,329 bytes; physical page numbers coincide with the printed ones). Physical pp. 4--6 (Section 3 with Subsections 3.1--3.3 and displays (3.1), (3.2); Section 4 with (4.1)--(4.3); Section 5 with Theorem 5.1, (5.1), its proof and (5.2)) and p. 17 (Appendix A) were read in full, every display checked against the page image. Physical pp. 2--3 (Section 1, Subsection 1.1, Lemmas 2.1 and 2.2) were read in full for the definitions and the imported lemmas, and p. 1 for the theorem and scope only. Page images rendered and read: pp. 2, 3, 4, 5 and 6 at 110 dpi and p. 17 at 130 dpi.

Allowed material read: the four input pages the page cites, as of the same time (the normalization page and the Lemma 2.1, 2.2 and 2.3 reconstructions), their Statement sections as the interface; the provenance paragraph of the library card; the Statement section of the card's theorem result page; the statement of Problem 354 on wiki/problems/additive_bases/E0354/_index.md; docs/verification.md "Whole-claim report" and "Audit checklist"; docs/evidence.md "Source fidelity"; and docs/math_authoring.md.

Exposures: (1) the library card's _index.md printed whole, so its Read status, Overview, Standing, Bears on and Results sections reached the reviewer beyond the provenance paragraph; (2) the problem page has no Statement heading, and while locating the statement its frontmatter description, its Formulation paragraph and the opening lines of its Status paragraph reached the reviewer; (3) the four input pages printed whole, so their Source, Standing, Definitions and Proof sections reached the reviewer; only their Statement sections were used, except that the mesh lemma's proof was glanced at for the bound 2ci2c_i used in Step 5, which the Statement alone also gives; (4) a file listing of the folder as of that time showed the names evidence/_index.md and evidence/main.py; neither was opened. None of the exposed text entered the verdict.

Restatement

Setting (from the normalization page and pp. 2--3): α,β>0\alpha,\beta>0 with N=⌊β⌋<M=⌊α⌋<2NN=\lfloor\beta\rfloor<M=\lfloor\alpha\rfloor<2N and N≥2N\ge2; weights ai=⌊2iα⌋a_i=\lfloor2^i\alpha\rfloor, bi=⌊2iβ⌋b_i=\lfloor2^i\beta\rfloor; conversions ui=ai+1−2aiu_i=a_{i+1}-2a_i, vi=bi+1−2biv_i=b_{i+1}-2b_i, both in {0,1}\{0,1\}; PnP_n the set of subset sums of the 2n2n weights of index below nn, each used at most once, the empty sum included; SnS_n their total; Ln=an+bnL_n=a_n+b_n; Dn=gcd⁡(an,bn)D_n=\gcd(a_n,b_n); Xn=Pn mod DnX_n=P_n\bmod D_n; hn=h(Xn)h_n=h(X_n). Conventions: for a nonempty residue set, hh is the length of the longest cyclic run of missing residues, 00 when the set is full; for a finite integer set with at least two elements, span is maximum minus minimum and gap is the largest difference of consecutive elements.

Hypotheses. Fix a layer n≥0n\ge0 and write d=Dnd=D_n, an=dpa_n=dp, bn=dqb_n=dq, so gcd⁡(p,q)=1\gcd(p,q)=1 and, by the interlacing bn<an<2bnb_n<a_n<2b_n, q<p<2qq<p<2q (whence q≥2q\ge2, p≥3p\ge3). Put S=SnS=S_n, X=XnX=X_n, H=hnH=h_n, k=max⁡(1,H)k=\max(1,H), so 1≤k≤d1\le k\le d. Fix ℓ≥1\ell\ge1 such that ui=vi=0u_i=v_i=0 for n≤i≤n+ℓ−2n\le i\le n+\ell-2 and (un+ℓ−1,vn+ℓ−1)≠(0,0)(u_{n+\ell-1},v_{n+\ell-1})\ne(0,0); write K=2ℓK=2^\ell, F=q(p−1)F=q(p-1), B∗=S+d(F+p+q)+22B_*=S+d(F+p+q)+22, K∗=2q(p−1)+4(p+q)+64K_*=2q(p-1)+4(p+q)+64, and assume K≥K∗K\ge K_*. Set r=n+ℓ+3r=n+\ell+3.

Conclusion. For every t≥rt\ge r,

ht≤max⁡(0,hn−1),h_t\le\max(0,h_n-1),

and this holds whatever the values of the conversions at indices ≥n+ℓ\ge n+\ell are (the conversions at n+ℓ−1n+\ell-1, n+ℓn+\ell, n+ℓ+1n+\ell+1 enter the construction only through constants bounded by 2222, and later ones only through the doubling bound on the weights). If hn≤1h_n\le1, then there is an integer H0H_0 such that every integer m≥H0m\ge H_0 lies in PtP_t for some tt; that is, the normalized pair is complete.

Length condition. With CM=16(M+1)2C_M=16(M+1)^2, the inequality ℓ≥2n+CM\ell\ge2n+C_M implies K≥K∗K\ge K_*; CMC_M depends on MM alone.

Checklist

  • Quantifiers and scope. Pass, with one clarification (F1). The conclusion is for all t≥rt\ge r, not eventually; the boundary cases d=1d=1 (then k=1k=1 and 64d−42=22=22d64d-42=22=22d), k=dk=d, ℓ\ell small (excluded by K≥K∗≥64K\ge K_*\ge64) and t=rt=r (span of WW at least brb_r directly) are handled on the page. The domain of "every choice of the later conversions" is left implicit; see F1.
  • Circularity. None. The proof consumes the three finite lemmas, the certificate table and prefix facts about the normalized pair; no descent or completeness statement enters its own proof.
  • Model and convention changes. None. The mesh WtW_t is an actual subset of PtP_t, and Xt⊇Wt mod DtX_t\supseteq W_t\bmod D_t is the actual residue set. The substitution p=2x+yp=2x+y, q=x+yq=x+y is an exact linear reparametrization of the open cone q<p<2qq<p<2q by x,y>0x,y>0; the reviewer checked both directions.
  • Finite and statistical overreach. None. The certificate is a finite check of 125125 nodes times four third-digit pairs, but each checked object is a linear form whose sign is decided on the whole cone, so the finite table covers every integer pair with q<p<2qq<p<2q. The reviewer re-derived the table independently (Strongest attack).
  • Uniformity. Pass. B∗B_* and K∗K_* depend on the layer data d,p,q,Sd,p,q,S and the page says so; the descent bound is uniform in every later conversion; CMC_M depends on MM only, and the page states this.
  • Extremal conclusions. Inapplicable: the page claims no infimum, supremum, sharpness or attained value. (The reviewer's instances below show that gap⁡(W)=k\operatorname{gap}(W)=k and ht=k−1h_t=k-1 can be attained, so the bounds are not slack; the page does not claim this either way.)
  • Consequences and composition. Pass, with F3. Each "hence" was re-derived: (3.1) to the Claim to (3.2); (4.1) to the nonemptiness and pairwise intersection of the shortened node intervals; (4.2) to (4.3); the mesh lemma to the projection lemma to (5.1); k=1k=1 to completeness. The prefix bound Sn<LnS_n<L_n is consumed in Step 4 without a citation and is missing from the Scope paragraph's list of inputs (F3).
  • Computation. Pass as far as this review reaches. The folder's evidence was excluded and not run. The reviewer's own computation reconstructed the coefficients from the masks of p. 17 under the stated bit order and found no failing instance of conditions 1--3, and simulated three concrete layers with randomized continuations without a violation of (4.2), (4.3) or (5.1).
  • Reproduction. Not performed by design: the page's evidence entry point, the source's standalone checker and its Lean kernel evaluation are outside the commissioned read set, and the page claims no rerun line that this review could check. The page's Standing paragraph says the source's checker and Lean evaluation were not replayed, which is consistent with author-recorded standing.
  • Source and verdict fidelity. Pass. The statement, hypotheses, displays (3.1), (3.2), (4.1)--(4.3), (5.1), (5.2), the section titles and every locator (pp. 4--6, p. 17, seventeen pages) match the artifact. The Standing paragraph claims author-recorded status only. Two readings are not marked as readings (F1, F4), and supplied steps are not marked (F5).

Weakest steps

W1. The endpoint bounds of Step 2 (why B∗B_* suffices). Let z∈J=[dKL+B∗, dKU−B∗]z\in J=[dKL+B_*,\,dKU-B_*] with z mod d∈X+cz\bmod d\in X+c, where σ0=dKl0+c\sigma_0=dKl_0+c, L=max⁡(l0,l1)≥l0L=\max(l_0,l_1)\ge l_0 and U=min⁡(l0,l1)+p+q≤l0+p+qU=\min(l_0,l_1)+p+q\le l_0+p+q. Choose f∈Pnf\in P_n with f≡z−c(modd)f\equiv z-c\pmod d, so d∣z−σ0−fd\mid z-\sigma_0-f, and 0≤f≤S0\le f\le S. Then

z−σ0−f ≥ dKL+B∗−dKl0−c−S ≥ B∗−c−S=d(F+p+q)+22−c ≥ dF,z-\sigma_0-f\ \ge\ dKL+B_*-dKl_0-c-S\ \ge\ B_*-c-S=d(F+p+q)+22-c\ \ge\ dF,

using c≤22c\le22, and

z−σ0−f ≤ dK(l0+p+q)−B∗−dKl0 = dK(p+q)−S−d(F+p+q)−22 ≤ d[(p+q)(K−1)−F],z-\sigma_0-f\ \le\ dK(l_0+p+q)-B_*-dKl_0\ =\ dK(p+q)-S-d(F+p+q)-22 \ \le\ d\bigl[(p+q)(K-1)-F\bigr],

using S≥0S\ge0. So (z−σ0−f)/d(z-\sigma_0-f)/d is an integer in [F,(p+q)(K−1)−F][F,(p+q)(K-1)-F], and (3.1), which needs only K≥pK\ge p (here K≥K∗>4pK\ge K_*>4p), writes it as px+qypx+qy with 0≤x,y<K0\le x,y<K. The binary digits of xx and yy select distinct block weights 2jdp2^jdp, 2jdq2^jdq (j<ℓj<\ell); ff uses indices below nn and σ0\sigma_0 indices n+ℓn+\ell to n+ℓ+2n+\ell+2; the three index groups are disjoint, so z∈Prz\in P_r. The case z mod d∈X+c+1z\bmod d\in X+c+1 is the same with σ1\sigma_1 and c+1≤22c+1\le22. This composes with the erosion lemma: the residue set (X∪(X+1))+c(X\cup(X+1))+c has longest missing run max⁡(0,H−1)≤k−1\max(0,H-1)\le k-1, and k≤dk\le d consecutive integers occupy kk distinct cyclically consecutive residues, so one of them is present; that is (3.2).

W2. The window cover of Step 4 and gap⁡(W)≤k\operatorname{gap}(W)\le k. With li=dKLi+B∗l_i=dKL_i+B_*, ri=dKUi−B∗r_i=dKU_i-B_* and each of Ui−LiU_i-L_i, Ui−Li+1U_i-L_{i+1}, Ui+1−LiU_{i+1}-L_i at least 11, (4.1) gives ri−lir_i-l_i, ri−li+1r_i-l_{i+1} and ri+1−lir_{i+1}-l_i all at least dK−2B∗≥22d≥k−1dK-2B_*\ge22d\ge k-1. Hence each Ji−=[li,ri−k+1]J_i^-=[l_i,r_i-k+1] is nonempty and max⁡(li,li+1)≤min⁡(ri,ri+1)−k+1\max(l_i,l_{i+1})\le\min(r_i,r_{i+1})-k+1, so Ji−∩Ji+1−J_i^-\cap J_{i+1}^- is nonempty; by induction on ii the union J1−∪⋯∪Ji−J_1^-\cup\cdots\cup J_i^- is one integer interval, since each new member meets the previous one. Its endpoints are min⁡ili≤l1≤L∗\min_il_i\le l_1\le L_* and max⁡i(ri−k+1)≥rs−k+1≥U∗−k+1\max_i(r_i-k+1)\ge r_s-k+1\ge U_*-k+1 by condition 3, so it contains [L∗,U∗−k+1][L_*,U_*-k+1], a nonempty interval because U∗−L∗=dK(6p−4q)−2B∗≥22d>k−1U_*-L_*=dK(6p-4q)-2B_*\ge22d>k-1. Every window [z,z+k−1]⊆I[z,z+k-1]\subseteq I therefore has z∈Ji−z\in J_i^- for some ii, lies inside JiJ_i, and by (3.2) meets PrP_r, hence W=Pr∩IW=P_r\cap I. The window at L∗L_* gives min⁡W≤L∗+k−1\min W\le L_*+k-1, the window ending at U∗U_* gives max⁡W≥U∗−k+1\max W\ge U_*-k+1, and consecutive w<w′w<w' in WW with w′−w≥k+1w'-w\ge k+1 would leave [w+1,w+k]⊆(w,w′)⊆I[w+1,w+k]\subseteq(w,w')\subseteq I without a point of WW. So WW has at least two elements, gap⁡(W)≤k\operatorname{gap}(W)\le k and span⁡(W)≥U∗−L∗−2(k−1)\operatorname{span}(W)\ge U_*-L_*-2(k-1); with br=8dKq+8v1+4v2+2v3+vn+ℓ+2≤8dKq+15b_r=8dKq+8v_1+4v_2+2v_3+v_{n+\ell+2}\le8dKq+15 and U∗−L∗−(8dKq+15)=dK(6p−4q)−2B∗−15≥22d−15U_*-L_*-(8dKq+15)=dK(6p-4q)-2B_*-15\ge22d-15, one gets span⁡(W)−br≥20d−13>0\operatorname{span}(W)-b_r\ge20d-13>0.

W3. The chain from the mesh lemma to (5.1). The weights of index at least rr in increasing order are br<ar<br+1<ar+1<⋯b_r<a_r<b_{r+1}<a_{r+1}<\cdots, each at most twice its predecessor (ai<2bia_i<2b_i; bi+1≤2bi+1≤2aib_{i+1}\le2b_i+1\le2a_i as ai≥bi+1a_i\ge b_i+1). Adding them one at a time to WW produces Wt=W+P(ai,bi:r≤i<t)W_t=W+P(a_i,b_i:r\le i<t) after the 2(t−r)2(t-r) weights of indices below tt, since W+P(c1,…,cj)=(W+P(c1,…,cj−1))∪(W+P(c1,…,cj−1)+cj)W+P(c_1,\ldots,c_j)=(W+P(c_1,\ldots,c_{j-1}))\cup(W+P(c_1,\ldots,c_{j-1})+c_j). The consequence of the mesh lemma applies because span⁡(W)≥br\operatorname{span}(W)\ge b_r and gap⁡(W)≤k\operatorname{gap}(W)\le k: every WtW_t has gap at most kk, minimum min⁡W\min W, and span span⁡(W)+∑r≤i<t(ai+bi)\operatorname{span}(W)+\sum_{r\le i<t}(a_i+b_i). For t>rt>r this span is at least 2at−1≥bt2a_{t-1}\ge b_t, since the span before adding at−1a_{t-1} was at least at−1a_{t-1} (the reviewer checked that this also follows from the statement alone: cj−i≥2−icjc_{j-i}\ge2^{-i}c_j and span⁡(W)≥c1≥21−jcj\operatorname{span}(W)\ge c_1\ge2^{1-j}c_j, so span⁡(W)+c1+⋯+cj−1≥cj(21−j+∑i=1j−12−i)=cj\operatorname{span}(W)+c_1+\cdots+c_{j-1}\ge c_j\bigl(2^{1-j}+\sum_{i=1}^{j-1}2^{-i}\bigr)=c_j); for t=rt=r the span is at least brb_r by (4.3). As Dt≤btD_t\le b_t, the projection lemma with m=Dtm=D_t gives h(Wt mod Dt)≤k−1h(W_t\bmod D_t)\le k-1, and Wt⊆PtW_t\subseteq P_t (its elements use indices below rr and indices in [r,t)[r,t), disjointly) gives Xt⊇Wt mod DtX_t\supseteq W_t\bmod D_t; a superset of residues has no longer missing run, so ht≤k−1=max⁡(0,hn−1)h_t\le k-1=\max(0,h_n-1). When k=1k=1 each WtW_t is the full interval [min⁡W,max⁡Wt][\min W,\max W_t] with max⁡Wt→∞\max W_t\to\infty, so every integer at least min⁡W\min W lies in some PtP_t.

Strongest attack

The only input the page does not prove is the certificate lemma, whose truth the page delegates to a finite check the reviewer could not read. The reviewer therefore attacked it from the artifact alone. From the Appendix A table on p. 17 (text layer, cross-read against the page image) the reviewer reconstructed, for each node (m0,m1,J)(m_0,m_1,J), the two subset sums of the six post-block weights under the stated bit order (a1a_1, b1b_1, a2a_2, b2b_2 from the least significant bit; JJ adding neither, a3a_3, b3b_3 or both), as linear forms in p,qp,q with digit-dependent constants, for all twelve templates and all four third-digit pairs. The table has 1212 rows with 9,9,9,12,9,9,12,11,11,11,13,109,9,9,12,9,9,12,11,11,11,13,10 nodes, 125125 in all, hence 113113 consecutive links, matching the page and the source. Condition 1 held at every instance with constants at most 1919. For condition 2 the reviewer first proved that the pointwise statement "min⁡(l0,l1)+p+q−max⁡(l0′,l1′)≥1\min(l_0,l_1)+p+q-\max(l_0',l_1')\ge1 for all integers q<p<2qq<p<2q" is equivalent to positivity on the open cone of each of the four forms la+p+q−lb′l_a+p+q-l_b', because a pointwise minimum of finitely many forms is positive at a point exactly when each form is, and a form positive at every integer point of the open cone is nonnegative on the closed cone and not identically zero; then the cone test (2a+b≥02a+b\ge0, a+b≥0a+b\ge0, not both zero, after p=2x+yp=2x+y, q=x+yq=x+y) was applied to the four forms at each of the 125125 nodes and the eight forms at each of the 113113 links, 14041404 forms in all (they depend on the masks and JJ, not on the third digits), and the closed-cone test to the two forms of condition 3 at each chain end. No form failed. As a control on the reduction, the min-max inequalities were also evaluated directly at the integer points (p,q)=(3,2)(p,q)=(3,2), (5,3)(5,3), (7,4)(7,4), (9,5)(9,5), (11,6)(11,6), (101,100)(101,100), (199,100)(199,100) and (1999,1000)(1999,1000), the last three near the cone's two boundary rays; none was violated. One chain, template (1,0),(0,0)(1,0),(0,0), was also worked by hand: its nine nodes give (Li,Ui)(L_i,U_i) equal to (2p,2p+2q)(2p,2p+2q), (3p,3p+2q)(3p,3p+2q), (p+4q,p+6q)(p+4q,p+6q), (2p+4q,2p+6q)(2p+4q,2p+6q), (3p+4q,3p+6q)(3p+4q,3p+6q), (2p+7q,4p+6q)(2p+7q,4p+6q), (5p+4q,5p+6q)(5p+4q,5p+6q), (6p+4q,6p+6q)(6p+4q,6p+6q), (7p+4q,7p+6q)(7p+4q,7p+6q), with every cross margin one of 2q−p2q-p, p−qp-q, 2p−2q2p-2q, 6q−2p6q-2p, 3p−q3p-q or p+2qp+2q, all positive on the cone, L1=2p≤p+2qL_1=2p\le p+2q and U9=7p+6qU_9=7p+6q.

The second attack aimed at the mesh bounds themselves, looking for slack that a wrong constant would expose. At layer n=1n=1 with (a0,b0)=(12,8)(a_0,b_0)=(12,8) and (a1,b1)=(24,16)(a_1,b_1)=(24,16), so d=8d=8, p=3p=3, q=2q=2, S=20S=20, X={0,4}X=\{0,4\}, H=3H=3, k=3k=3, ℓ=7\ell=7, K=128≥K∗=92K=128\ge K_*=92, B∗=114B_*=114 and I=[7282,33678]I=[7282,33678], the reviewer formed PrP_r for every template and third-digit pair with randomized ten-digit continuations (9696 runs): gap⁡(W)\operatorname{gap}(W) was exactly 3=k3=k in the worst run, span⁡(W)−br≥9995\operatorname{span}(W)-b_r\ge9995, and ht≤1h_t\le1 for r≤t<r+9r\le t<r+9. At d=16d=16 with (a1,b1)=(48,32)(a_1,b_1)=(48,32), X={0,8}X=\{0,8\} modulo 1616, H=7H=7, k=7k=7: the worst gap was 7=k7=k and the worst hth_t was 6=k−16=k-1, the bound attained. At d=1d=1, n=0n=0, (a0,b0)=(3,2)(a_0,b_0)=(3,2): WW was a full interval and ht=0h_t=0 throughout. The bounds are tight and were never crossed, so the attack failed.

A third attack looked for a hidden hypothesis. The candidate was the sorted-order and doubling claim of Step 5 for weights after index rr under "every choice of the later conversions": if the conversions are abstract 0/10/1 digits rather than the actual floors, the normalization page's item 4 does not literally apply. The attack fails because interlacing persists under any digits: from bi<ai<2bib_i<a_i<2b_i, ai+1≥2ai≥2bi+2>2bi+1≥bi+1a_{i+1}\ge2a_i\ge2b_i+2>2b_i+1\ge b_{i+1} and ai+1≤2ai+1≤4bi−1<2bi+1a_{i+1}\le2a_i+1\le4b_i-1<2b_{i+1}. It leaves a clarification (F1), not a defect.

Premises

  • Lemma 2.1 (erosion). Interface: for nonempty X⊆Z/dZX\subseteq\mathbb Z/d\mathbb Z, h(X∪(X+1))=max⁡(0,h(X)−1)h(X\cup(X+1))=\max(0,h(X)-1). Source held, p. 3, read in full; the reconstruction's Statement read. Applied to X=Pn mod dX=P_n\bmod d, nonempty since 0∈Pn0\in P_n, then translated by cc, which preserves hh. Imported; the page names it by link and the Scope paragraph counts it among the "three finite lemmas".
  • Lemma 2.2 (mesh) with its consequence. Interface: if span⁡(W)≥c>0\operatorname{span}(W)\ge c>0 and gap⁡(W)≤k\operatorname{gap}(W)\le k then W∪(W+c)W\cup(W+c) has gap at most kk and span span⁡(W)+c\operatorname{span}(W)+c; for c1≤c2≤⋯c_1\le c_2\le\cdots with ci+1≤2cic_{i+1}\le2c_i and span⁡(W0)≥c1\operatorname{span}(W_0)\ge c_1, every iterate keeps gap at most kk, the same minimum and span span⁡(W0)+c1+⋯+ci\operatorname{span}(W_0)+c_1+\cdots+c_i. Source held, p. 3, read in full; the reconstruction's Statement read. Hypotheses met by (4.2), (4.3) and the interlacing order. Imported.
  • Lemma 2.3 (projection). Interface: if span⁡(W)≥m≥1\operatorname{span}(W)\ge m\ge1 and gap⁡(W)≤k\operatorname{gap}(W)\le k then h(W mod m)≤k−1h(W\bmod m)\le k-1. Source held, p. 4, read in full; the reconstruction's Statement read. Applied with m=Dt≤bt≤span⁡(Wt)m=D_t\le b_t\le\operatorname{span}(W_t). Imported.
  • Normalized-pair facts. Interface: ui,vi∈{0,1}u_i,v_i\in\{0,1\}; bi<ai<2bi≤bi+1b_i<a_i<2b_i\le b_{i+1} with the merged list increasing and each term at most twice its predecessor; Sn<LnS_n<L_n; an<2n(M+1)a_n<2^n(M+1). Source held, pp. 2--3, read in full; the normalization page's Statement read, its proofs not audited here (they are author-recorded reconstructions). The page cites the interlacing but not Sn<LnS_n<L_n (F3).
  • The certificate table. Interface: the twelve chains of Appendix A satisfy conditions 1--3 of the page's Certificate lemma for all four third-digit pairs and all integers q<p<2qq<p<2q. Source held, p. 17, read in full from the text layer and the page image; independently re-derived by the reviewer (Strongest attack). The page delegates the check to the folder's evidence, which this review did not read.
  • Explicit assumptions. The sequences continue forever (an infinite index set); the conversions are 0/10/1 digits; the block hypotheses of Section 3 with K≥K∗K\ge K_*. No batch acceptance order applies.

Findings

F1. Severity: suggested. Location: Statement, "for every choice of the later conversions". Defect: the domain of the quantifier is implicit. The page's Definitions bind the weights to the fixed normalized pair, under which the later conversions admit exactly one choice, while the source (p. 6, Theorem 5.1) says "for every legal continuation", and the page's own hypotheses call (u2,v2)(u_2,v_2), (u3,v3)(u_3,v_3) "arbitrary". Under the free-digit reading, Step 5's sorted-order and doubling claim rests on the normalization page's item 4, proved there for floor sequences only. Witness: p. 6, "for every legal continuation and every t≥rt\ge r"; the page's Step 5, "The weights of indices ≥r\ge r in sorted order are br<ar<br+1<⋯b_r<a_r<b_{r+1}<\cdots, each at most twice its predecessor". Proposed replacement: after the Statement add "Here the conversions at indices ≥n+ℓ−1\ge n+\ell-1 may be any digits in {0,1}\{0,1\}, the weights being defined from (an,bn)=(dp,dq)(a_n,b_n)=(dp,dq) by the recurrences; interlacing persists under any digits, since bi<ai<2bib_i<a_i<2b_i gives ai+1≥2ai≥2bi+2>bi+1a_{i+1}\ge2a_i\ge2b_i+2>b_{i+1} and ai+1≤2ai+1≤4bi−1<2bi+1a_{i+1}\le2a_i+1\le4b_i-1<2b_{i+1}, so the sorted-order and doubling facts of Step 5 hold for every continuation."

F2. Severity: suggested. Location: Step 4, "br=8dKq+8v1+4v2+2v3+v4b_r=8dKq+8v_1+4v_2+2v_3+v_4". Defect: the symbol v4v_4 is not defined on the page; only (u1,v1)(u_1,v_1), (u2,v2)(u_2,v_2), (u3,v3)(u_3,v_3) are. Witness: the page's Definitions define three conversion pairs; br=2bn+ℓ+2+vn+ℓ+2b_r=2b_{n+\ell+2}+v_{n+\ell+2} by the recurrence of p. 2. Proposed replacement: "br=8dKq+8v1+4v2+2v3+v4b_r=8dKq+8v_1+4v_2+2v_3+v_4, where v4=vn+ℓ+2v_4=v_{n+\ell+2} is the conversion at index r−1r-1, so br≤8dKq+15b_r\le8dKq+15."

F3. Severity: suggested. Location: Step 4, "Since S=Sn<Ln=d(p+q)S=S_n<L_n=d(p+q) is an integer", and Scope, "Its only inputs beyond the three finite lemmas are the certificate table and the interlacing of the normalized pair". Defect: the prefix bound Sn<LnS_n<L_n is consumed without a citation and is absent from the Scope paragraph's inventory; it is not a consequence of interlacing but of the column identity aj−∑i<jai=M+∑i<juia_j-\sum_{i<j}a_i=M+\sum_{i<j}u_i (p. 3, end of Subsection 1.1), which the source lists among the Section 3 setup as "S=Sn<d(p+q)S=S_n<d(p+q)" (p. 4). Proposed replacement: in the Hypotheses of Section 3 write "Put E=PnE=P_n and S=SnS=S_n; then S<Ln=d(p+q)S<L_n=d(p+q) by item 6 of the normalization page", and in Scope "Its only inputs beyond the three finite lemmas are the certificate table, the interlacing and digit bounds of the normalized pair, and the prefix bound Sn<LnS_n<L_n."

F4. Severity: note. Location: Hypotheses of Section 3, "suppose the conversions at indices n,…,n+ℓ−2n,\ldots,n+\ell-2 are zero while the conversion at index n+ℓ−1n+\ell-1 is nonzero". Defect: this is a reading of the source's "Use ℓ\ell exact doubling pairs at indices n,…,n+ℓ−1n,\ldots,n+\ell-1" (p. 4), which could also be read as ℓ\ell vanishing conversions starting at index n−1n-1; the page's reading is the one consistent with the displayed weights dKp+u1dKp+u_1 and the range 0≤x,y<K=2ℓ0\le x,y<K=2^\ell, and it is the weaker hypothesis, since the proof uses only an+j=2jdpa_{n+j}=2^jdp for 0≤j≤ℓ−10\le j\le\ell-1. It is not marked as a reading. Proposed replacement: append "(this reads the source's 'ℓ\ell exact doubling pairs' as the ℓ\ell pairs (2jdp,2jdq)(2^jdp,2^jdq), 0≤j<ℓ0\le j<\ell, which is all the proof uses)".

F5. Severity: suggested. Location: Source paragraph, and Steps 1, 3 and 6. Defect: the page does not say which steps it supplies, unlike its sibling pages ("the proof below writes them out"). Supplied and unmarked are the remark q≥2q\ge2; the detailed overlap argument of Step 1 (the source, p. 4, says only "They intersect because q<pq<p"); the reduction of condition 2 to four forms in Step 3 (the source, p. 5, describes the checker's cone inequalities without stating this reduction); the explicit window-intersection inequalities of Step 4; the bound 2at−1≥bt2a_{t-1}\ge b_t of Step 5; and the whole derivation of K∗<16p2K_*<16p^2 in Step 6, which the source states without proof ("Since K∗≤16p2K_*\le16p^2", p. 6). Proposed replacement: add to the Source paragraph "The source proves (3.1), (3.2) and (4.1)--(4.3) in a few lines each and states K∗≤16p2K_*\le16p^2 without proof; the proof below supplies the deductions, in particular the four-form reduction of the certificate's condition 2 and the estimate of Step 6."

Verdict

Source fidelity: faithful. The statement, its hypotheses, the displays and every locator match the artifact at pp. 4--6 and 17, and the Standing paragraph claims only author-recorded status; the findings are clarifications of readings, one undefined symbol and an incomplete inventory of inputs, none of which alters the mathematics.

The argument as reconstructed: sound. Every essential deduction was re-derived by the reviewer, the certificate lemma was re-derived independently from the artifact's table with no failing instance, and concrete instances attained the bounds without crossing them.

Limitations: the folder's evidence, the source's standalone checker and its Lean formalization were neither read nor run; the proofs on the normalization and lemma pages were taken at their Statement interfaces and not audited; Sections 6--12 of the manuscript were not read, so how Theorem 5.1 is consumed downstream is outside this review; the reviewer's own computations are retained in this report as derivations, not as repository evidence.

This focused review assigns no tier and changes no status.