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A090246
The largest subset of P(Z/3Z)^n that does not contain 3 collinear points.
2
2, 4, 10, 20, 56
OFFSET
1,1
COMMENTS
P(Z/3Z)^n is the projective space of n dimensions over the finite field Z/3Z. This is the size of the largest subset which does not contain 3 points lying in a line.
Davis and Maclagan described a game similar to the game SET that could be played in this space using projective lines, rather than in (Z/3Z)^n using the algebraic notion of line. This sequence is the analog of A090245 for this game.
So far this sequence agrees with A104442.
LINKS
B. Davis and D. Maclagan, The Card Game SET, The Mathematical Intelligencer, Vol. 25:3 (Summer 2003), pp. 33-40.
B. L. Davis and D. Maclagan, The Card Game SET [From Omar E. Pol, Feb 21 2009]
Ivars Peterson, SET Math.
Ivars Peterson, SET Math [From Omar E. Pol, Feb 21 2009]
CROSSREFS
Cf. A090245.
Sequence in context: A026395 A247630 A015889 * A104442 A104434 A104433
KEYWORD
nonn,more
AUTHOR
Hans Havermann, Jan 23 2004
EXTENSIONS
Edited by Jack W Grahl, May 12 2009
STATUS
approved