On the size of a blocking set inPG(2,p)


We show that the size of a non-trivial blocking set in the Desarguesian projective planePG(2,p), wherep is prime, is at least 3(p+1)/2. This settles a 25 year old conjecture of J. di Paola.

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Blokhuis, A. On the size of a blocking set inPG(2,p). Combinatorica 14, 111–114 (1994). https://doi.org/10.1007/BF01305953

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AMS subject classification code (1991)

  • 05 B 25