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Source. Proposition 8, p. 9, of Wouter van Doorn, Completeness of exponentially increasing sequences, arXiv:2602.23394v1 (25 February 2026), the version named on the source card. A preprint.

Read depth. Claims checked: the statement was read clause by clause on the page images of the print; the description of the search was read, and the search data were not run. Nothing here is independently reviewed.

Statement

Setting (p. 1). For positive reals tt and α\alpha, St(α)=(s1,s2,…)S_t(\alpha)=(s_1,s_2,\ldots) with sn=⌊tαn⌋s_n=\lfloor t\alpha^n\rfloor, indexed from n=1n=1. For a sequence or multiset SS of positive integers, P(S)P(S) is the set of integers that are sums of distinct elements of SS; SS is complete when N∖P(S)\mathbb N\setminus P(S) is finite and entirely complete when P(S)=NP(S)=\mathbb N. Throughout, φ=(1+5)/2\varphi=(1+\sqrt5)/2.

Proposition 8 (p. 9). St(α)S_t(\alpha) is complete

  • for all t≤3t\le3 if 1.3<α≤1.41.3<\alpha\le1.4;
  • for all t≤5t\le5 if 1.2<α≤1.31.2<\alpha\le1.3;
  • for all t≤10t\le10 if 1.1<α≤1.21.1<\alpha\le1.2;
  • for all t≤50t\le50 if 1<α≤1.11<\alpha\le1.1.

Proof pointer

Computer-assisted (pp. 9--10). The region is covered by rectangles; for each rectangle the terms common to the sequences at its bottom-left and top-right corners, together with the range of one further term, are shown to meet the hypothesis of Lemma 5 for every pair in the rectangle, and a rectangle that fails is split into four. The partitions are published in the author's repository (https://github.com/Woett/Complete-sequences-data). For α≤1.2\alpha\le1.2 the search uses t≥2t\ge2 by Proposition 7, and for α≤1.1\alpha\le1.1 it uses α≥1.015\alpha\ge1.015 by Proposition 9 (p. 10).

Dependencies

Lemma 5, Proposition 7, Proposition 9, and the published search data.

Bears on

  • Problem 349: every pair in the four stated boxes gives a complete sequence, on the strength of the computer search; the search data were not checked here.