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Subject and independence

Role: independent reviewer in a fresh context, given only the commission. The reviewer took no part in writing the subject page, the reconstruction pages of the folder, or any earlier review of them. Charge: refutation of the author-recorded mathematics of one section.

Subject: page wiki/research/erdos_18/connections.md as it stood at 2026-09-28T13:50:48Z, section ## Shared lemmas, lines 47–243 (from the H2 heading to the line before ## Problem 304). The subject page is the lead page; no other lead was named.

Read in full as of the same time: the section; the page's preamble (lines 1–46, the standing sentence and the Conventions paragraph) as an input; the reconstruction pages hughes_lemma_4_reconstruction.md, hughes_theorem_1_reconstruction.md, hughes_corollary_3_reconstruction.md, doorn_lemma_3_1_reconstruction.md, doorn_lemma_3_3_reconstruction.md, doorn_corollary_3_4_reconstruction.md, doorn_proposition_4_1_reconstruction.md and doorn_theorem_1_1_reconstruction.md of the folder, taken as premises at their reviewed standing; the Statement paragraphs of wiki/problems/divisors/E0018/_index.md, wiki/problems/unit_fractions/E0304/_index.md and wiki/problems/unit_fractions/E0293/_index.md; the provenance paragraphs of the two library cards; the held PDFs, namely Hughes (2026) p. 2 on the page image (Theorem 2 as quoted, Corollary 3, Lemma 4) with the extracted text of pp. 1–3, and van Doorn (2026) pp. 2, 3 and 6 on the page images (Lemma 3.1 with its proof, Lemma 5.1 with its proof) with the extracted text of pp. 1, 4 and 5 (the definitions of Q(k)Q(k) and t(k)t(k), Lemma 3.3, Corollary 3.4, Proposition 4.1); docs/verification.md sections "Grading and claim standing", "Audit checklist", "Whole-claim report" and the shared audit checklist; docs/approach_vetting.md; docs/evidence.md section "Source fidelity"; docs/math_authoring.md.

Exposures. (1) The three problem pages carry, between their Statement and their first H2, a bold Status paragraph with known bounds and proof-claim summaries, and their frontmatter desc and status fields; these were printed together with the Statement and were read. No Current assessment or Known results section was read. (2) The two library cards' generated link rows, their Read status and Bears on paragraphs, and the opening of the Hughes card's Overview were printed with the provenance paragraph and were read. (3) The reconstruction pages carry Standing paragraphs that describe their sources' standing; they were read as parts of those pages. Nothing under any evidence/ folder, no _index.md, no other section's review and no web search was consulted.

Restatement

Throughout, h(N)h(N) is the page's fresh-set count over 1≤m≤N1\le m\le N, practical means every 1≤m≤N1\le m\le N is a sum of distinct divisors of NN, τ\tau is the divisor count and logarithms are natural unless subscripted.

S1 (Lemma A). Let N≥1N\ge1 be an integer such that v2(N)≥⌊log⁡2p⌋v_2(N)\ge\lfloor\log_2p\rfloor for every odd prime pp dividing NN. Then (a) any two consecutive divisors d<bd<b of NN satisfy b≤2db\le2d; (b) by the consequence clause of the Lemma 4 page, the greedy expansion of every 1≤m≤N1\le m\le N terminates and writes mm as a sum of distinct divisors of NN, so NN is practical; (c) h(N)≤log⁡2N+1h(N)\le\log_2N+1; (d) the hypothesis holds for N=n!N=n! for every n≥1n\ge1, for N=lcm(1,…,x)N=\mathrm{lcm}(1,\dots,x) for every x≥1x\ge1, and for N=pjMN=p^jM whenever it holds for MM, pp is an odd prime, j≥1j\ge1 and ⌊log⁡2p⌋≤v2(M)\lfloor\log_2p\rfloor\le v_2(M).

S2 (Lemma B). Let NN have property (a) of S1, let T≥2T\ge2 be real with 2T≤N2T\le\sqrt N, let δ ⁣:[T,N]→(0,1/8]\delta\colon[T,\sqrt N]\to(0,1/8] be nonincreasing, and suppose every pair of consecutive divisors d<bd<b of NN with T≤db≤NT\le\sqrt{db}\le\sqrt N has log⁡(b/d)≤12δ(db)\log(b/d)\le\frac12\delta(\sqrt{db}). Put σ(ℓ)=log⁡(1/δ(eℓ/2))\sigma(\ell)=\log(1/\delta(e^\ell/2)) for log⁡(2T)≤ℓ≤12log⁡N\log(2T)\le\ell\le\frac12\log N. Then σ\sigma is nondecreasing, σ≥log⁡8\sigma\ge\log8, and

h(N)≤3∫log⁡(2T)12log⁡Ndℓσ(ℓ)+log⁡2σ(12log⁡N)+2log⁡2(2T)+5,h(N)\le3\int_{\log(2T)}^{\frac12\log N}\frac{d\ell}{\sigma(\ell)} +\log_2\sigma\bigl(\tfrac12\log N\bigr)+2\log_2(2T)+5 ,

with the constants 33, 22 and 55 absolute.

S3 (Lemma C). Let n≥b≥2n\ge b\ge2 be integers with nn practical and 1≤a<b1\le a<b. Then there are s+t≤2h(n)s+t\le2h(n) distinct integers greater than 11 whose reciprocals sum to a/ba/b, of which ss are divisors of nn (in (1,n](1,n]) and tt are of the form bn/ebn/e with e∣ne\mid n, each greater than nn. If b∤nb\nmid n, none of them equals bb.

S4 (Lemma C′). Let bb be a sufficiently large integer, nn the least integer with n!≥bn!\ge b, pp the least prime not dividing nn, and N=n!N=n! if b∤n!b\nmid n!, else N=pj(n−1)!N=p^j(n-1)! with j=⌈log⁡n/log⁡p⌉j=\lceil\log n/\log p\rceil. Then NN is practical, N≥bN\ge b, b∤Nb\nmid N, and h(N)≤max⁡(h(n!),h((n−1)!)+⌈log⁡2n⌉)h(N)\le\max(h(n!),h((n-1)!)+\lceil\log_2n\rceil). The parenthetical asserts p≤n−1p\le n-1 and p≪log⁡np\ll\log n.

S5 (Lemma D, first inequality). For every practical n0n_0 and every chain nj+1=Ajnjn_{j+1}=A_jn_j, 0≤j<J0\le j<J, with Aj≥2A_j\ge2, in which every residue modulo AjA_j is a sum of at most LjL_j distinct divisors of njn_j, Lj≥log⁡Aj/log⁡(τ(nj)+1)L_j\ge\log A_j/\log(\tau(n_j)+1) for each jj, hence for the sums over j<Jj<J.

S6 (Lemma D, second inequality). Under the hypotheses of S5,

∑j<Jlog⁡Ajlog⁡(τ(nj)+1)≥(12log⁡2−ϵ(nJ))(log⁡log⁡nJ)2\sum_{j<J}\frac{\log A_j}{\log(\tau(n_j)+1)} \ge\Bigl(\frac1{2\log2}-\epsilon(n_J)\Bigr)(\log\log n_J)^2

with ϵ(x)→0\epsilon(x)\to0 as x→∞x\to\infty, where, as written ("uniformly over all such chains"), ϵ\epsilon depends on neither the chain nor its seed n0n_0.

S7 (Lemma D, "Hence" sentence). For every such chain, h(n0)+∑j<JLj≥(1/(2log⁡2)−ϵ(nJ))(log⁡log⁡nJ)2h(n_0)+\sum_{j<J}L_j\ge(1/(2\log2)-\epsilon(n_J))(\log\log n_J)^2 with the same ϵ\epsilon; this includes J=0J=0, where the chain is the seed alone.

S8 (closing paragraph). (a) No certificate built from Lemma 3.1 extensions alone from a fixed seed can prove h(N)≤(log⁡log⁡N)2−ηh(N)\le(\log\log N)^{2-\eta} for any fixed η>0\eta>0, or h(N)≤c(log⁡log⁡N)2h(N)\le c(\log\log N)^2 with c<1/(2log⁡2)c<1/(2\log2), for all large NN along the chain. (b) In the van Doorn chain each step costs 44 while log⁡Aj/log⁡τ(nj)→6/7\log A_j/\log\tau(n_j)\to6/7. (c) Its primes of size k6log⁡kk^6\log k make log⁡τ(nj)\log\tau(n_j) about one sixth of the maximal order (log⁡2)log⁡nj/log⁡log⁡nj(\log2)\log n_j/\log\log n_j. (d) c0=14/log⁡2≈20.2c_0=14/\log2\approx20.2 is 2828 times 1/(2log⁡2)≈0.721/(2\log2)\approx0.72.

Checklist

  • Quantifiers and scope: defect in S6 and S7. "Let n0n_0 be practical" quantifies the seed universally and "uniformly over all such chains" removes the seed from the error term; under that reading S6 is false (F1) and S7 is unproved (F2). S1–S5 and S8 state their quantifiers exactly; S8 carries the "fixed seed" clause that S6 and S7 lack.
  • Circularity: pass. No statement is assumed in its own proof; Lemma A reproves the ratio property rather than citing the Lemma 4 page's factorial case, and Lemma D's floor uses only counting and an external maximal-order bound.
  • Model and convention changes: pass. The page's hh (over m≤Nm\le N) is the convention of the Lemma 4, Theorem 1 and Lemma 3.1 pages, and Lemma C uses it only for q<nq<n and r<nr<n, so the site's hh also serves. Lemma B transports the Theorem 1 count to an arbitrary profile; the bridge (facts (i) and (ii) and Lemma 4 hold for every NN) was checked, not assumed from the shape of the formulas.
  • Finite and statistical overreach: pass. No finite check is used as a proof on the page. Lemma C′'s "sufficiently large" is honest: b=2b=2 gives n=2n=2, p=3>n−1p=3>n-1 and N=3N=3, which is not practical. The exact checks reported below are attacks, not warrants.
  • Uniformity: defect in S6 (F1). The proof's Oη(1)O_\eta(1) silently contains (log⁡log⁡n0)2(\log\log n_0)^2 when the seed already exceeds the Wigert threshold. Lemma B's constants are explicit and absolute; Lemma A's bound is explicit; Lemma C′'s bound is explicit in nn.
  • Extremal conclusions: pass with F2. The floor of Lemma D is stated in its own units, (log⁡log⁡nJ)2(\log\log n_J)^2 with the constant 1/(2log⁡2)1/(2\log2), and the "never below" of S7 is exactly the sentence that overreaches for unrestricted seeds. The arithmetic of S8(d), 28=(4/(6/7))⋅628=(4/(6/7))\cdot6, was recomputed.
  • Consequences and composition: pass except F2. Lemma A's "Consequently" was checked against the Lemma 4 page's consequence clause; Lemma C′ composes Lemma A with Lemma 3.1 and supplies every hypothesis of the latter (A=p≥2A=p\ge2, seed practical, residues by one divisor each, total at most the seed, no summand divisible by pp); Lemma D's "Hence" is F2.
  • Computation: pass. The page computes only 2828, 6/76/7, 0.720.72 and 20.220.2; all were recomputed. The reviewer's own exact checks are described under Strongest attack with their coverage.
  • Reproduction: inapplicable. The section states no rerun command and no coverage claim.
  • Source and verdict fidelity: pass with a note (F5). Lemma C matches Lemma 5.1 on the p. 6 image clause for clause; Lemma 3.1's interface matches p. 2; "pays 44 per step" matches Corollary 3.4 on p. 5; Q(k)=k6log⁡kQ(k)=k^6\log k and t(k)t(k) match p. 4; Lemma 4 and Corollary 3 match Hughes p. 2. The attribution "as the Problem 304 page records" lies outside the read set.

Weakest steps

W1 (Lemma D, the asymptotic floor). Write ℓj=log⁡nj\ell_j=\log n_j and f(ℓ)=log⁡ℓ/ℓf(\ell)=\log\ell/\ell, decreasing for ℓ>e\ell>e. The maximal order of τ\tau gives log⁡(τ(n)+1)≤(log⁡2+η′(n))log⁡n/log⁡log⁡n\log(\tau(n)+1)\le(\log2+\eta'(n))\log n/\log\log n with η′(n)→0\eta'(n)\to0; fix η>0\eta>0 and a threshold n(η)n(\eta) beyond which η′≤η\eta'\le\eta and log⁡n>e\log n>e. For nj≥n(η)n_j\ge n(\eta), S5 gives Lj≥(ℓj+1−ℓj)f(ℓj)/(log⁡2+η)L_j\ge(\ell_{j+1}-\ell_j)f(\ell_j)/(\log2+\eta), and because ff decreases, the left Riemann sum over j≥j(η)j\ge j(\eta) dominates ∫ℓj(η)ℓJf=12((log⁡ℓJ)2−(log⁡ℓj(η))2)\int_{\ell_{j(\eta)}}^{\ell_J}f=\frac12\bigl((\log\ell_J)^2-(\log\ell_{j(\eta)})^2\bigr). If j(η)≥1j(\eta)\ge1, the step j(η)−1j(\eta)-1 has nj(η)−1<n(η)n_{j(\eta)-1}<n(\eta), so by S5 and τ(n)≤n\tau(n)\le n its cost is at least (ℓj(η)−log⁡n(η))/log⁡(2n(η))(\ell_{j(\eta)}-\log n(\eta))/\log(2n(\eta)), linear in ℓj(η)\ell_{j(\eta)}; this exceeds (log⁡ℓj(η))2(\log\ell_{j(\eta)})^2 once ℓj(η)≥C(η)\ell_{j(\eta)}\ge C(\eta), and otherwise (log⁡ℓj(η))2≤(log⁡C(η))2(\log\ell_{j(\eta)})^2\le(\log C(\eta))^2. Either way ∑jLj≥(log⁡ℓJ)2/(2(log⁡2+η))−Oη(1)\sum_jL_j\ge(\log\ell_J)^2/(2(\log2+\eta))-O_\eta(1), and letting η→0\eta\to0 gives S6 with ϵ\epsilon depending only on nJn_J. If j(η)=0j(\eta)=0, that is n0≥n(η)n_0\ge n(\eta), nothing compensates the subtracted (log⁡ℓ0)2=(log⁡log⁡n0)2(\log\ell_0)^2=(\log\log n_0)^2: the argument yields only ∑jLj≥((log⁡log⁡nJ)2−(log⁡log⁡n0)2)/(2(log⁡2+η))\sum_jL_j\ge\bigl((\log\log n_J)^2-(\log\log n_0)^2\bigr)/(2(\log2+\eta)), which is empty when nJn_J is a bounded multiple of n0n_0. The witness in F1 shows this is not a weakness of the proof but of the statement.

W2 (Lemma B, the upper range). For a nonterminal remainder N<R≤N/(2T)\sqrt N<R\le N/(2T) with bracketing divisors d<R<bd<R<b, put U=N/RU=N/R, so 2T≤U<N2T\le U<\sqrt N. The map x↦N/xx\mapsto N/x reverses the divisor order, so N/b<U<N/dN/b<U<N/d are consecutive divisors with ratio b/db/d. From d>R/2d>R/2 and b<2Rb<2R (property (a) of S1) one has R/2<db<2RR/\sqrt2<\sqrt{db}<\sqrt2R, hence U/2<N/db<2UU/\sqrt2<N/\sqrt{db}<\sqrt2U; fact (ii) of the Theorem 1 page (R>NR>\sqrt N forces db≥Ndb\ge N) gives N/db≤NN/\sqrt{db}\le\sqrt N, and U≥2TU\ge2T gives N/db>2T≥TN/\sqrt{db}>\sqrt2T\ge T. So the hypothesis applies to the mirror pair: log⁡(b/d)≤12δ(N/db)≤12δ(U/2)\log(b/d)\le\frac12\delta(N/\sqrt{db})\le\frac12\delta(U/2), the last by monotonicity since N/db>U/2≥TN/\sqrt{db}>U/2\ge T. Lemma 4 at the actual remainder gives R′=R−d≤2Rlog⁡(b/d)≤R δ(U/2)R'=R-d\le2R\log(b/d)\le R\,\delta(U/2), so log⁡U′−log⁡U≥σ(log⁡U)\log U'-\log U\ge\sigma(\log U). The starts log⁡Ui\log U_i of the upper-range steps increase and lie in [log⁡(2T),12log⁡N)[\log(2T),\frac12\log N). With Jk={ℓ:2klog⁡8≤σ(ℓ)<2k+1log⁡8}J_k=\{\ell:2^k\log8\le\sigma(\ell)<2^{k+1}\log8\}, an interval because σ\sigma is monotone, the starts in JkJ_k form a run, consecutive members of which differ by at least σ(log⁡Ui)≥2klog⁡8\sigma(\log U_i)\ge2^k\log8; so MkM_k starts in JkJ_k force ∣Jk∣≥(Mk−1)2klog⁡8|J_k|\ge(M_k-1)2^k\log8, while ∫Jkdℓ/σ≥∣Jk∣/(2k+1log⁡8)\int_{J_k}d\ell/\sigma\ge|J_k|/(2^{k+1}\log8), giving Mk≤1+2∫Jkdℓ/σM_k\le1+2\int_{J_k}d\ell/\sigma. There are at most K=⌊log⁡2(σ(12log⁡N)/log⁡8)⌋+1K=\lfloor\log_2(\sigma(\frac12\log N)/\log8)\rfloor+1 classes. Adding the lower range (1+∫1+\int), the two endgames (each at most log⁡2(2T)+1\log_2(2T)+1 halving steps) and the terminal divisor gives 3∫+K+2log⁡2(2T)+4≤3∫+log⁡2σ(12log⁡N)+2log⁡2(2T)+5−log⁡2log⁡83\int+K+2\log_2(2T)+4\le3\int+\log_2\sigma(\tfrac12\log N)+2\log_2(2T)+5-\log_2\log8, which is below the stated bound. The lower-range charging needs σ\sigma at the upper end of each step's interval to dominate the integrand, which nondecreasing σ\sigma supplies; the last lower-range step may leave [log⁡(2T),12log⁡N][\log(2T),\frac12\log N] and is counted by the 11.

W3 (Lemma C′, the second case). If b∣n!b\mid n!, then b∤(n−1)!b\nmid(n-1)! because (n−1)!<b(n-1)!<b by the minimality of nn (for n≥2n\ge2). For N=pj(n−1)!N=p^j(n-1)! with p∤np\nmid n, gcd⁡(n!,N)=(n−1)!gcd⁡(n,pj)=(n−1)!\gcd(n!,N)=(n-1)!\gcd(n,p^j)=(n-1)!, so b∣Nb\mid N together with b∣n!b\mid n! would give b∣(n−1)!b\mid(n-1)!, a contradiction; and pj≥np^j\ge n gives N≥n!≥bN\ge n!\ge b. For the practicality and the cost, the residues 1≤c≤p−11\le c\le p-1 modulo pp are each a single divisor of (n−1)!(n-1)!, hence of pi(n−1)!p^i(n-1)!, not divisible by pp and of total c≤pi(n−1)!c\le p^i(n-1)!, and the residue 00 is the empty sum; this is the hypothesis of Lemma 3.1 with A=pA=p and L=1L=1, valid exactly when p−1≤n−1p-1\le n-1, that is p≤np\le n, which with p∤np\nmid n is p≤n−1p\le n-1. Applying Lemma 3.1 jj times from the practical number (n−1)!(n-1)! (Lemma A) gives h(N)≤h((n−1)!)+jh(N)\le h((n-1)!)+j and j≤⌈log⁡2n⌉j\le\lceil\log_2n\rceil because p≥2p\ge2. The condition p≤n−1p\le n-1 holds for every n≥3n\ge3: if every prime below nn divided nn, their product would be at most nn, which fails for n≥4n\ge4, and n=3n=3 has p=2p=2. For n=2n=2 it fails (p=3p=3), which is the b=2b=2 case above.

Strongest attack

S1. The attack looked for an NN meeting the hypothesis with a divisor gap above 22, concentrating on odd primes just below a power of two, where p/2cp/2^c is close to 22 (for example N=4⋅7N=4\cdot7 and N=16⋅31N=16\cdot31), and on the proof's step v2(d)=v2(N)v_2(d)=v_2(N), which needs q=N/dq=N/d odd and is supplied by the case split. An exhaustive exact check of every N≤3000N\le3000 satisfying the hypothesis confirmed the ratio property, that the greedy divisors are distinct and sum to mm for every 1≤m≤N1\le m\le N, and that their number is at most ⌊log⁡2N⌋+1\lfloor\log_2N\rfloor+1; the hypothesis is not vacuous (N=10N=10 fails it and has the consecutive divisors 2<52<5). The factorial, lcm and pjMp^jM cases were rederived, including ⌊n/2⌋≥⌊log⁡2n⌋\lfloor n/2\rfloor\ge\lfloor\log_2n\rfloor for n≥4n\ge4 and the three values N=1,2,6N=1,2,6 for n≤3n\le3. The attack failed.

S2. The attack targeted the direction of monotonicity in each range (the lower range bounds a descent by σ\sigma at the upper end of the step's interval, the upper range an ascent by σ\sigma at the lower end, which is why the dyadic classes are needed), the domain of δ\delta at each evaluation (R/2R/2, U/2U/2, db\sqrt{db} and N/dbN/\sqrt{db} all lie in [T,N][T,\sqrt N] when R≥2TR\ge2T or U≥2TU\ge2T), the possibility of many starts in one class (excluded by the forced separation 2klog⁡82^k\log8), the boundary steps (the last lower-range step, counted by 11; runs whose last ascent leaves the interval, which the count of starts ignores) and the constant bookkeeping, which has slack log⁡2log⁡8\log_2\log8. The bookkeeping was also exercised on N=10!,11!,12!N=10!,11!,12! with δ\delta read off the actual gaps and TT the least power of two admissible under the hypothesis: the greedy steps of sampled mm in each of the four ranges stayed within that range's bound. The attack failed.

S3. The attack targeted distinctness across the two groups (settled by n/di≤n<bn/ejn/d_i\le n<bn/e_j), the degenerate cases r=0r=0 (empty second group) and q≥1q\ge1 (forced by an≥n≥ban\ge n\ge b), and the last clause, which fails without b∤nb\nmid n: for n=bn=b and a=1a=1 the representation is 1/b1/b itself. An exhaustive exact-rational check over every practical n≤48n\le48, every 2≤b≤n2\le b\le n and every 1≤a<b1\le a<b confirmed the sum, the distinctness, the bound 2h(n)2h(n) and the avoidance of bb when b∤nb\nmid n. The attack failed.

S4. The attack targeted the choice of pp (it must avoid nn, not bb; the gcd computation shows why), the case p=2p=2 for odd nn (the single residue 11), the inequality p≤n−1p\le n-1 (W3), and small bb: b=2b=2 breaks the lemma (N=3N=3), so "sufficiently large" cannot be removed, while an exact computation of hh for the factorials and prime-power multiples involved confirmed every clause for 3≤b≤20003\le b\le2000. The attack failed.

S5. Each residue class needs its own representing subset, since a subset has one sum. The number of subsets of a τ\tau-set with at most LL elements is ∑i≤L(τi)≤∑i≤L(Li)τi=(τ+1)L\sum_{i\le L}\binom\tau i\le\sum_{i\le L}\binom Li\tau^i=(\tau+1)^L. The attack failed.

S6. Witness: n0=2kn_0=2^k (practical by binary expansion), J=1J=1, A0=3A_0=3, L0=1L_0=1, since the residues 0,1,20,1,2 modulo 33 are the empty sum, the divisor 11 and the divisor 22, with totals at most n0n_0 and no summand divisible by 33; n1=3⋅2kn_1=3\cdot2^k. The middle term of the display is log⁡3/log⁡(k+2)<1\log3/\log(k+2)<1, the left is 11, and the right is (1/(2log⁡2)−ϵ(3⋅2k))(log⁡(klog⁡2+log⁡3))2→∞(1/(2\log2)-\epsilon(3\cdot2^k))(\log(k\log2+\log3))^2\to\infty for any ϵ→0\epsilon\to0 (about 30.930.9 at k=1000k=1000). The statement as written is refuted; W1 locates the gap. Restricted to seeds n0≤Cn_0\le C for a fixed CC, the proof of the page closes with the one-line addition that the subtracted (log⁡log⁡n0)2(\log\log n_0)^2 is then OC(1)O_C(1), and no attack against that version succeeded.

S7. The witness of S6 does not refute S7, because h(2k)=kh(2^k)=k. But for J=0J=0 and unrestricted seed, S7 reads h(n0)≥(1/(2log⁡2)−o(1))(log⁡log⁡n0)2h(n_0)\ge(1/(2\log2)-o(1))(\log\log n_0)^2 for every practical n0n_0, a lower bound for hh that the page itself disclaims ("not a lower bound for hh") and that no argument on the page supports; the counting bound gives only h(n)≥log⁡n/log⁡(τ(n)+1)≫log⁡log⁡nh(n)\ge\log n/\log(\tau(n)+1)\gg\log\log n. No disproof is known to the reviewer. For seeds bounded by a fixed CC, S7 follows from the repaired S6 since h(n0)≥0h(n_0)\ge0.

S8. (a) follows from the repaired S6 with h(n0)h(n_0) a constant. For (b), (c) and (d) the Lemma 3.3 and Proposition 4.1 pages give τ(nj)=(E+1)2kj\tau(n_j)=(E+1)2^{k_j}, AjA_j a product of t(kj)t(k_j) primes in (Q(kj),2Q(kj)](Q(k_j),2Q(k_j)] with Q(k)=k6log⁡kQ(k)=k^6\log k and t(k)=⌊klog⁡2/(7log⁡k+3log⁡log⁡k)⌋t(k)=\lfloor k\log2/(7\log k+3\log\log k)\rfloor, so log⁡Aj=t(kj)(6log⁡kj+O(log⁡log⁡kj))=(6/7+o(1))kjlog⁡2\log A_j=t(k_j)(6\log k_j+O(\log\log k_j))=(6/7+o(1))k_j\log2 and log⁡Aj/log⁡(τ(nj)+1)→6/7\log A_j/\log(\tau(n_j)+1)\to6/7; log⁡Vj=∑i<jt(ki)log⁡Q(ki)+O(1)\log V_j=\sum_{i<j}t(k_i)\log Q(k_i)+O(1) compares with 6∫kjlog⁡k dk6\int^{k_j}\log k\,dk, so log⁡nj∼6kjlog⁡kj\log n_j\sim6k_j\log k_j and the maximal order (log⁡2)log⁡nj/log⁡log⁡nj∼6kjlog⁡2(\log2)\log n_j/\log\log n_j\sim6k_j\log2 is six times log⁡τ(nj)∼kjlog⁡2\log\tau(n_j)\sim k_j\log2; and (14/log⁡2)/(1/(2log⁡2))=28=(4/(6/7))⋅6(14/\log2)/(1/(2\log2))=28=(4/(6/7))\cdot6. The van Doorn chain's certified cost 4j4j with j∼(c0/4)uj2j\sim(c_0/4)u_j^2 exceeds its own Lemma D sum ∼(6/7)j\sim(6/7)j by the factor 14/314/3 and the universal floor by 2828, consistently. The attack failed.

Premises

  • Lemma 4 page: for NN whose consecutive divisors have ratio at most 22 and a nonterminal remainder 1≤R≤N1\le R\le N with bracketing divisors d<R<bd<R<b, R−d<dR-d<d and R−d≤2Rlog⁡(b/d)R-d\le2R\log(b/d); the compilation-supplied consequence that the greedy expansion of every 1≤m≤N1\le m\le N terminates and writes mm as a sum of distinct divisors. Independently reviewed as of 2026-09-28T05:03:27Z per the commission; read in full; the source lemma checked on Hughes p. 2.
  • Theorem 1 page: facts (i) (R≤NR\le\sqrt N forces db≤Ndb\le N) and (ii) (R>NR>\sqrt N forces db≥Ndb\ge N), whose proofs use only that N/xN/x permutes the divisors, and the lower-range charging argument. Same standing; read in full.
  • Corollary 3 page: the conventions εj\varepsilon_j and the windows named in the page's Conventions; not otherwise consumed by the section. Read in full.
  • Lemma 3.1 page: for A≥2A\ge2 and practical nn, if every residue modulo AA is a sum of at most LL distinct divisors of nn with total at most nn and no summand divisible by AA, then AnAn is practical and h(An)≤h(n)+Lh(An)\le h(n)+L. Same standing; read in full; statement and proof checked on van Doorn pp. 2–3.
  • Lemma 3.3 page, Corollary 3.4 page, Proposition 4.1 page and Theorem 1.1 page: the definitions of Q(k)Q(k), t(k)t(k), c0c_0, the cost 44 per step, the construction nj=2EVjn_j=2^EV_j and its size estimates, used only for S8(b)–(d). Same standing (claimed results, reconstructed); read in full; checked against van Doorn pp. 4–6.
  • Hughes (2026), held: p. 2 read on the page image, pp. 1–3 in extracted text.
  • van Doorn (2026), held: pp. 2, 3, 6 read on the page images, pp. 1, 4, 5 in extracted text. Lemma 5.1 (p. 6) states exactly S3 and is called well known there.
  • Wigert's maximal order of τ\tau, used by Lemma D in the form log⁡τ(n)≤(log⁡2+η(n))log⁡n/log⁡log⁡n\log\tau(n)\le(\log2+\eta(n))\log n/\log\log n with η(n)→0\eta(n)\to0: a classical theorem, not held in the library, imported by the page without a citation; the form is the standard one and was accepted.
  • An elementary lower bound for the product of the primes below pp (Chebyshev type), silently behind the aside p≪log⁡np\ll\log n in Lemma C′; not held, not used by the proof (F4).
  • The Statement paragraphs of Problems 18, 304 and 293 for the conventions hh, N(a,b)N(a,b), N(b)N(b), DkD_k and v(k)v(k); read as stated.
  • Explicit assumptions of this review: the reconstruction pages are taken as established at their reviewed standing, and the Lemma 3.1 page's result is consumed as a claimed result whose proof was nevertheless rechecked on the source pages because Lemma C′ and Lemma D rest on its interface.

Findings

F1 (required). Location: Lemma D, Statement, "where the o(1)o(1) tends to 00 as nJ→∞n_J\to\infty uniformly over all such chains", together with "Let n0n_0 be practical". Defect: the second inequality is false when the seed is unrestricted; the proof handles the first index j(η)j(\eta) only when a step precedes it ("The step j(η)−1j(\eta)-1, if it exists"), and when it does not exist the subtracted (log⁡ℓj(η))2=(log⁡log⁡n0)2(\log\ell_{j(\eta)})^2=(\log\log n_0)^2 is absorbed into Oη(1)O_\eta(1) without justification. Witness: n0=2kn_0=2^k, J=1J=1, A0=3A_0=3, L0=1L_0=1, for which the middle term is log⁡3/log⁡(k+2)<1\log3/\log(k+2)<1 while the right side tends to infinity with kk. Replacement: "where, for each fixed CC, the o(1)o(1) tends to 00 as nJ→∞n_J\to\infty uniformly over all such chains with n0≤Cn_0\le C", and in the proof, after "the other steps contribute nonnegatively": "if j(η)=0j(\eta)=0, then ℓj(η)=log⁡n0≤log⁡C\ell_{j(\eta)}=\log n_0\le\log C and the subtracted term is OC(1)O_C(1)", with Oη(1)O_\eta(1) read as Oη,C(1)O_{\eta,C}(1).

F2 (required). Location: Lemma D, Statement, "Hence the bound h(n0)+∑jLjh(n_0)+\sum_jL_j that such a chain certifies for h(nJ)h(n_J) is never below (1/(2log⁡2)−o(1))(log⁡log⁡nJ)2(1/(2\log2)-o(1))(\log\log n_J)^2." Defect: for unrestricted seeds this sentence, at J=0J=0, asserts the lower bound h(n0)≥(1/(2log⁡2)−o(1))(log⁡log⁡n0)2h(n_0)\ge(1/(2\log2)-o(1))(\log\log n_0)^2 for every practical n0n_0, which the page does not prove and elsewhere disclaims; the sentence is proved only for seeds bounded by a fixed CC, which is what the following paragraph's "from a fixed seed" means. Witness: none for a disproof; the defect is an unsupported inference. Replacement: "Hence, for chains from seeds n0≤Cn_0\le C, the bound h(n0)+∑jLjh(n_0)+\sum_jL_j that such a chain certifies for h(nJ)h(n_J) is never below (1/(2log⁡2)−o(1))(log⁡log⁡nJ)2(1/(2\log2)-o(1))(\log\log n_J)^2."

F3 (suggested). Location: Lemma D, Proof, "let j(η)j(\eta) be the least index with nj(η)≥n(η)n_{j(\eta)}\ge n(\eta)". Defect: n(η)n(\eta) is not defined; the proof needs it to satisfy both η′(n)≤η\eta'(n)\le\eta for n≥n(η)n\ge n(\eta) and log⁡n(η)>e\log n(\eta)>e, the latter so that ff decreases on the range of the Riemann sum. Replacement: define n(η)n(\eta) by these two properties before introducing j(η)j(\eta).

F4 (note). Location: Lemma C′, Statement, "(so p≤n−1p\le n-1: the primes dividing nn have product at most nn, whence p≪log⁡np\ll\log n)". Defect: the "whence" imports a lower bound for the product of the primes below pp without saying so, and the proof uses only p≤n−1p\le n-1, which holds for every n≥3n\ge3 (W3); the lemma's "large" is still needed, as b=2b=2 shows. Replacement: "(so p≤n−1p\le n-1 for n≥3n\ge3, since the primes below nn cannot all divide nn once n≥4n\ge4)"; drop p≪log⁡np\ll\log n or mark it as an unused aside.

F5 (note). Location: Lemma C, preamble, "it is the transfer behind Erdős's 1950 bound and behind Vose's, as the Problem 304 page records". The attribution to the Problem 304 page lies outside this review's read set and was not checked; the note's own introduction (pp. 1–2) supports the mathematical attribution. No replacement proposed.

Verdict

  • S1 (Lemma A): refutation-failed.
  • S2 (Lemma B): refutation-failed.
  • S3 (Lemma C): refutation-failed.
  • S4 (Lemma C′): refutation-failed.
  • S5 (Lemma D, first inequality): refutation-failed.
  • S6 (Lemma D, second inequality with the o(1)o(1) uniform over all chains): refuted-as-stated, by the witness of F1; the same inequality with the seed bounded by a fixed constant survived every attack once the proof receives the one-line addition of F1.
  • S7 (Lemma D, "Hence" sentence): proof defective; statement unresolved, for unrestricted seeds (F2); it follows from the repaired S6 for seeds bounded by a fixed constant.
  • S8 (closing paragraph, fixed-seed obstruction and the van Doorn accounting): refutation-failed, its "from a fixed seed" being exactly the hypothesis the repaired S6 needs.

Limitations. Wigert's maximal order and the Berend–Harmse conventions were accepted as imported; the reconstruction pages were consumed at their reviewed standing and the note's results remain claimed; the exact checks cover only the stated finite ranges and warrant nothing beyond the derivations they accompany. This focused review assigns no tier and changes no status.