Nuclei of sets of q + 1 points in PG(2, q) and blocking sets of Redei type
نویسندگان
چکیده
منابع مشابه
The size of minimal blocking sets of Q(4, q)
Let Q(2n+2, q) denote the non-singular parabolic quadric in the projective geometry PG(2n+2, q). We describe the implementation in GAP of an algorithm to determine the minimal number of points of a minimal blocking set of Q(4, q), for q = 5, 7
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In this paper, k-blocking sets in PG(n, q), being of Rédei type, are investigated. A standard method to construct Rédei type k-blocking sets in PG(n, q) is to construct a cone having as base a Rédei type k′-blocking set in a subspace of PG(n, q). But also other Rédei type k-blocking sets in PG(n, q), which are not cones, exist. We give in this article a condition on the parameters of a Rédei ty...
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Intriguing sets of vertices have been studied for several classes of strongly regular graphs. In the present paper, we study intriguing sets for the graphs Γn, n ≥ 2, which are defined as follows. Suppose Q(2n, 2), n ≥ 2, is a nonsingular parabolic quadric of PG(2n, 2) and Q+(2n − 1, 2) is a nonsingular hyperbolic quadric obtained by intersecting Q(2n, 2) with a suitable nontangent hyperplane. ...
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We characterize the smallest minimal blocking sets of Q(2n, q), q an odd prime, in terms of ovoids of Q(4, q) and Q(6, q). The proofs of these results are written for q = 3, 5, 7 since for these values it was known that every ovoid of Q(4, q) is an elliptic quadric. Recently, in [2], it has been proven that for all q prime, every ovoid of Q(4, q) is an elliptic quadric. Since as many proofs as ...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 1990
ISSN: 0097-3165
DOI: 10.1016/0097-3165(90)90051-w