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Search: id:A085577
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| A085577 |
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Size of maximal subset of the n^2 nodes in an n X n grid such that there at least 3 edges between any pair of nodes. |
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+0
2
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| 1, 1, 2, 4, 6, 8, 10, 13, 17, 20, 25, 29, 34
(list; graph; listen)
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OFFSET
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1,3
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COMMENT
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The 1-neighborhoods of the nodes must be disjoint: i.e. this is a 1-error correcting code.
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FORMULA
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a(n) approaches n^2/5 as n -> infinity.
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EXAMPLE
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For example, a(3) = 2 (*'s indicate the chosen nodes):
o--o--*
|..|..|
o--o--o
|..|..|
*--o--o
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CROSSREFS
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Main diagonal of A085576.
Sequence in context: A096182 A056827 A024172 this_sequence A121832 A006586 A022292
Adjacent sequences: A085574 A085575 A085576 this_sequence A085578 A085579 A085580
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KEYWORD
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nonn,more,nice
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AUTHOR
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njas, Jul 08 2003
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