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On sets of points with few odd secants

  • Simeon Ball (a1) and Bence Csajbók (a2)


We prove that, for q odd, a set of q + 2 points in the projective plane over the field with q elements has at least 2qc odd secants, where c is a constant and an odd secant is a line incident with an odd number of points of the set.


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The first author acknowledges the support of project MTM2017-82166-P of the Spanish Ministerio de Economía y Competitividad.

The second author is supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences. The second author acknowledges the support of OTKA grant K 124950.



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On sets of points with few odd secants

  • Simeon Ball (a1) and Bence Csajbók (a2)


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