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Statement

The notions of a configuration and of an EE-Ramsey configuration are on the definitions page. The paper quotes two results of Kříž, citing Theorems 3.2 and 4.1 of his 1991 paper (p. 3).

Product. If F1F_1 is E1E_1-Ramsey and F2F_2 is E2E_2-Ramsey, then F1×F2F_1\times F_2 is (E1×E2)(E_1\times E_2)-Ramsey; the same holds for finite products. The product relation is taken coordinatewise: two points are related when each pair of corresponding coordinates is related (p. 4).

Orbit gluing. Suppose FF is EE-Ramsey and b:F→Fb:F\to F is an isometry respecting EE. For z∈Fz\in F and r≥1r\ge1, let U(E;z,b,r)U(E;z,b,r) be the smallest equivalence relation containing EE in which z,bz,…,br−1zz,bz,\ldots,b^{r-1}z are equivalent. Then FF is U(E;z,b,r)U(E;z,b,r)-Ramsey.

The paper uses the product statement to pass from a configuration to its (n+1)(n+1)-fold power, and orbit gluing only with r=2r=2, both in the proof of Theorem 3.2. Kříž's own statements are recorded on his card as Theorem 3.2 and Theorem 4.1.

Source. Section 3, p. 3, with the coordinatewise product relation on p. 4, of Mostafa Mirabi, One-point extensions of Euclidean Ramsey sets, arXiv:2608.11736v1 (12 August 2026), the version named on the source card. The original is I. Kříž, Permutation groups in Euclidean Ramsey theory, Proc. Amer. Math. Soc. 112 (1991), no. 3, 899–907.

Read depth. Claims checked: Mirabi's statements were read clause by clause on the page image. Their proofs are Kříž's and are not part of this paper.

Proof pointer

Not proved in this paper; see the Kříž card.

Dependencies

None within this paper.

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