Minimal blocking sets in finite planes (Q1184584)

The author uses a previous paper [ibid., 166-177 (1992; see the paper above)] to characterize all minimal blocking sets of \(PG(2,q)\) with size \(q+n\) and at least two \(n\)-secants. This result is then applied in conjunction with the work of \textit{A. Blokhuis} and \textit{A. E. Brouwer} [Bull. Lond. Math. Soc. 18, 132-134 (1986; Zbl 0563.05016)] to prove the following interesting Theorem. Let \(B\) be a minimal blocking set of size \(s<q+\sqrt{2q}+1\) in \(PG(2,q)\). Then either \(q\) is a square and \(B\) a Baer subplane, or \(q=3\) or 5 and \(B\) is a projective triangle.