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arXiv · 2503.20529

Local obstructions in sequences revisited

Matthieu Rosenfeld·Alexander Shen
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Abstract

In this article, we consider some simple combinatorial game and a winning strategy in this game. This game is then used to prove several known results about non-repetitive sequences and approximations with denominators from a lacunary sequence. In this way we simplify the proofs, improve the bounds and get for free the computable versions that required a separate treatment.

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Matthieu Rosenfeld, Alexander Shen. 2025-03-26. Local obstructions in sequences revisited. https://arxiv.org/abs/2503.20529

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