Nuclei of point sets of sizeq+1 contained in the union of two lines inPG(2,q)


We give a complete classification for pairs (\(\mathcal{N}\)(ℬ),ℬ) where\(\mathcal{N}\)(ℬ) is the set of all nuclei of a set ℬ ofq+1 not collinear points contained in the union of two lines in a desarguesian planePG(2,q) of orderq. We also obtain some new results concerning blocking sets of Rédei type and certain point-sets of type [0,1,m,n] inPG(2, q).

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Korchmáros, G., Mazzocca, F. Nuclei of point sets of sizeq+1 contained in the union of two lines inPG(2,q). Combinatorica 14, 63–69 (1994).

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AMS subject classification code (1980)

  • 51 E 15