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Covering the integers by arithmetic sequences
Zhi-Wei Sun, Covering the integers by arithmetic sequences, Acta Arithmetica 72 (1995), no. 2, 109–129, IMPAN entry, DOI.
The Markdown reading copy beside the PDF records the real-sequence conventions, the finite-block threshold stated in the introduction, and the full displayed statement of Theorem 1. The source statements are recorded without a complete proof reconstruction or independent proof review.
The retained ICM mirror PDF has 21 pages and carries the journal's printed pages 109–129. Its first and Theorem 1 pages identify the article and pagination; the PDF metadata identifies a TeX/pdfTeX production, so the version is cited as this exact journal-paginated mirror copy. The file's text layer carries no copyright or license line; the publisher's record labels the PDF download "Pobierz zgodnie z CC-BY", which the English site renders "Free download under CC-BY license", naming no version or license URL (https://www.impan.pl/get/doi/10.4064/aa-72-2-109-129, read 2026-10-02).
The introductory finite-block result specializes at zero repeated common differences to Problem 275. The exact-cover conventions and Theorem 1 also give qualified background for Problem 947; the source does not assert the distinct-modulus impossibility in that problem.