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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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Pages below are those of the arXiv version 1012.1350v1 identified in the source digest.
Theorems used in the proofs
- Ramsey's theorem (finite form; the paper gives it no citation, its general reference for Ramsey theory being [8], Graham, Rothschild and Spencer, Ramsey Theory, Wiley, 1980): for positive integers with , some makes every -coloring of the -subsets of constant on the -subsets of some -set. Used for two-letter templates (p. 12) and twice in Theorem 3.1 (pp. 12--14).
- Van der Waerden's theorem (reference [14], Beweis einer Baudetschen Vermutung, Nieuw Arch. Wisk. 15 (1927), 212--216): every -coloring of a long enough interval has a monochromatic arithmetic progression of length . Used in Theorem 3.1 with .
- Orthogonal equivalence of representations: Lemma 4.7.1 of Wolf, Spaces of Constant Curvature, McGraw-Hill, 1967 (reference [15]), cited in the proof of Theorem 4.2 (p. 17); see the countability step.
- Sard's theorem, through Milnor, Topology from the Differentiable Viewpoint, 1965 (reference [13]), cited at the end of the proof of Lemma 4.1 (p. 16) for the nullity of a lower-dimensional smooth image.
The Hales--Jewett theorem (reference [9]) is mentioned for comparison only (pp. 6--7): without the fixed size , Conjectures C and D would follow from it. It is not used in a proof.
Earlier results the paper recalls
- Finite Ramsey witnesses by compactness (p. 5).
- Ramsey sets are spherical, products of Ramsey sets are Ramsey and bricks are Ramsey (p. 2).
- Coloring by distance from the origin, the idea behind the paper's four-coloring that avoids copies of (p. 2).
- Non-degenerate simplices are Ramsey and Kříž's soluble-group theorem (p. 2).
The paper also cites Cantwell on the -cell, Johnson on subtransitive sets, and Kříž's trapezoid paper (p. 18) as background; none of them enters a proof.
Bears on. Problem 174: background to the paper's results, which bear on the problem as their own pages state.
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