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A000509
Size of second largest n-arc in PG(2,q), where q runs through the primes and prime powers >= 7.
2
6, 6, 8, 10, 12, 13, 14, 14, 17, 21, 22, 24
OFFSET
1,1
COMMENTS
The Davydov et al. reference arXiv:10004.2817 has data sufficient for a b-file. - Jonathan Vos Post, Apr 18 2010
The terms run through indices q=A000961(i), i>=6. - R. J. Mathar, Jan 09 2017
LINKS
Alexander A. Davydov, Giorgio Faina, Stefano Marcugini, Fernanda Pambianco, New sizes of complete arcs in PG(2,q), arXiv:1004.2817 [math.CO], April 16, 2010.
Alexander A. Davydov, Giorgio Faina, Stefano Marcugini, Fernanda Pambianco, On sizes of complete caps in projective spaced PG(n,q) and arcs in planes PG(2,q), J. Geom. 94 (1) (2009) 31-58.
J. W. P. Hirschfeld, Complete arcs, Discr. Math., 174 (1997), 177-184.
J. W. P. Hirschfeld and L. Storme, The packing problem in statistics, coding theory and finite projective spaces, J. Statist. Plann. Inference 72 (1998), no. 1-2, 355-380.
G. Keri, Types of superregular matrices and the number of n-arcs and complete n-arcs in PG(r,q), Journal of Combinatorial Designs, Vol. 14 (2006), pp. 363-390.
EXAMPLE
m'(31)=22 because there are no complete n-arcs in PG(2,31) for 23<=n<=31.
CROSSREFS
Cf. A000510.
Cf. A000961.
Sequence in context: A322292 A195707 A175217 * A160257 A315830 A183042
KEYWORD
nonn,hard,more,nice
AUTHOR
J. W. P. Hirschfeld [ jwph(AT)sussex.ac.uk ]
EXTENSIONS
Definition clarified by G. Keri (keri(AT)sztaki.hu), Jan 03 2008
STATUS
approved