Classification of minimal blocking sets in PG(2, 9)

Abstract

A full classification (up to equivalence) of all minimal blocking sets in PG(2, 9) was obtained by computer. The resulting numbers of minimal blocking sets are tabulated according to size of the set and order of the automorphism group. For the minimal blocking sets with the larger automorphism groups explicit (geometric) descriptions are given. Some of these results can also be generalised to Desarguesian projective planes of higher order. We also give a complete list of all blocking semiovals in PG(2, 9) (up to equivalence). Mathematics Subject Classification (2020). 51E21, 51-04.