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Claim. P. Erdős, Remarks on some problems in number theory, Math. Balkanica 4 (1974), 197--202, papers presented at the Fifth Balkan Mathematical Congress, gives on p. 199 an improvement, due to Burgess and himself, of Meier's upper bound for the least c(n)c(n) such that the unit nn-cube splits into kk homothetic cubes for every k≥c(n)k\ge c(n), the quantity of Problem 769. Its display (2) is

c(n)≤(2n−2)((n+1)n−2)−1.c(n)\le(2^n-2)\bigl((n+1)^n-2\bigr)-1.

The proof replaces one cube of a decomposition by knk^n smaller cubes, so every ∑k=2n+1ck(kn−1)\sum_{k=2}^{n+1}c_k(k^n-1) with ck≥1c_k\ge1 is a tile count; the numbers kn−1k^n-1, 2≤k≤n+12\le k\le n+1, have no common factor (the paper's lemma), and a theorem of Brauer on representations by a set of coprime integers bounds the largest gap. The paper adds that a sharper theorem of Brauer gives c(n)<αnn+1c(n)<\alpha n^{n+1} for an absolute constant α\alpha, which it calls not hard to prove and does not prove. The source card is Erdős (1974).

Covers. The displayed upper bound for every nn, as part of the request for good bounds; the bound c(n)≪nn+1c(n)\ll n^{n+1} is stated without proof. Not covered: the order of c(n)c(n) and the question whether c(n)≫nnc(n)\gg n^n.

Depends on. No page of this wiki; the paper's lemma is restated on the source card's lemma page.

Acceptance. None on record. The volume collects the papers of a congress, with no evidence that it was refereed, and the site, which credits the bound c(n)≪nn+1c(n)\ll n^{n+1} to Burgess and Erdős, labels the problem OPEN.