Counting arcs in projective planes via Glynn’s algorithm

被引:3
作者
Kaplan N. [1 ]
Kimport S. [2 ]
Lawrence R. [3 ]
Peilen L. [3 ]
Weinreich M. [3 ]
机构
[1] Department of Mathematics, University of California, Irvine, 92697, CA
[2] Department of Mathematics, Stanford University, Stanford, 94305, CA
[3] Department of Mathematics, Yale University, New Haven, 06511, CT
基金
美国国家科学基金会;
关键词
Arcs; configurations of points and lines; finite projective planes; incidence structures; linear spaces; non-Desarguesian projective planes;
D O I
10.1007/s00022-017-0391-1
中图分类号
学科分类号
摘要
An n-arc in a projective plane is a collection of n distinct points in the plane, no three of which lie on a line. Formulas counting the number of n-arcs in any finite projective plane of order q are known for n≤ 8. In 1995, Iampolskaia, Skorobogatov, and Sorokin counted 9-arcs in the projective plane over a finite field of order q and showed that this count is a quasipolynomial function of q. We present a formula for the number of 9-arcs in any projective plane of order q, even those that are non-Desarguesian, deriving Iampolskaia, Skorobogatov, and Sorokin’s formula as a special case. We obtain our formula from a new implementation of an algorithm due to Glynn; we give details of our implementation and discuss its consequences for larger arcs. © 2017, Springer International Publishing.
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收藏
页码:1013 / 1029
页数:16
相关论文
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