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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Claim. M. Hudelson, Dissecting dd-cubes into smaller dd-cubes, J. Combin. Theory Ser. A 81 (1998), no. 2, 190--200, proves that c(d)=O((2d)d−1)c(d)=O((2d)^{d-1}), where c(d)c(d) is the least integer such that the unit dd-cube splits into kk homothetic cubes for every k≥c(d)k\ge c(d), and that c(d)<6dc(d)<6^d whenever gcd⁡(2d−1,3d−1)=1\gcd(2^d-1,3^d-1)=1; more generally c(d)=O((2k)d)c(d)=O((2k)^d) whenever gcd⁡(2d−1,kd−1)=1\gcd(2^d-1,k^d-1)=1, and the paper derives specific bounds for d≤5d\le5. The paper's abstract states these results, and the zbMATH review of the paper (Zbl 0891.05018) states the general bound and reports the paper's bound c(4)≤809c(4)\le809. These are upper bounds on the quantity that Problem 769 asks to bound; the general bound improves by a factor of order nn the bound (2n−2)((n+1)n−2)−1(2^n-2)((n+1)^n-2)-1 that Burgess and Erdős proved, which has order 2nnn2^nn^n.

Covers. The upper bound c(n)≪(2n)n−1c(n)\ll(2n)^{n-1} for every nn, the bound c(n)<6nc(n)<6^n under the stated gcd condition, and the bound c(4)≤809c(4)\le809, as part of the request for good bounds. Not covered: the order of c(n)c(n) and the question whether c(n)≫nnc(n)\gg n^n, which these upper bounds do not decide: the bound 6n6^n would answer it no if infinitely many nn met the gcd condition, which Erdős conjectured and which is not known.

Depends on. No page of this wiki.

Acceptance. refereed: Journal of Combinatorial Theory, Series A 81 (1998), no. 2, 190--200, February 1998. The site credits the result in its remarks on the problem, which it labels OPEN, so that remark is not acceptance and no reviewed is listed.