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A003142
Largest subset of 3 X 3 X ... X 3 cube (in n dimensions) with no 3 points collinear.
(Formerly M1611)
2
0, 2, 6, 16, 43, 124, 353
OFFSET
0,2
COMMENTS
The D. H. J. Polymath collective found a(5) and a(6) and gives the bound a(n) >= (2 + o(1))*binomial(n, i)*2^i for any i (and note that this is maximized by i near 2n/3). - Charles R Greathouse IV, Jun 11 2013
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
K. O'Bryant, Sets of Natural Numbers with Proscribed Subsets, J. Int. Seq. 18 (2015) # 15.7.7.
V. Chvatal, Edmonds polytopes and a hierarchy of combinatorial problems, Discr. Math. 4 (1973) no 4, 305-337.
D. H. J. Polymath, Density Hales-Jewett and Moser numbers, arXiv:1002.0374 [math.CO], 2010.
CROSSREFS
Sequence in context: A295572 A372191 A027068 * A335686 A118041 A105073
KEYWORD
nonn,hard,more
STATUS
approved