Abstract
We give estimates for the cardinality of the sets A , B ⊆ {1, 2,...,N} with the property that ab + 1 is squarefree for all a ∈ A, b ∈ B .
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Gyarmati, K. On divisibility properties of integers of the form ab + 1. Periodica Mathematica Hungarica 43, 71–79 (2002). https://doi.org/10.1023/A:1015229531017
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DOI: https://doi.org/10.1023/A:1015229531017