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Search: id:A121386
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| A121386 |
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Number of different colorings of {1,...,n} that minimize the number of three-term arithmetic progressions that such a coloring can contain. |
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2
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| 2, 4, 6, 10, 14, 20, 16, 6, 36, 8, 44, 10, 8, 30, 16, 8, 12, 2, 12, 28, 64, 110, 96, 134, 56, 44, 16, 2, 16, 74, 116, 188, 200, 180
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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The unique (up to switching colors) sequences for n=18 and n=28 are 001001111000011011 and 0001100011111100000011100111 respectively.
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EXAMPLE
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a(3)=6 because all non-monochromatic colorings are such an example
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CROSSREFS
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Cf. A121385.
Adjacent sequences: A121383 A121384 A121385 this_sequence A121387 A121388 A121389
Sequence in context: A024204 A036641 A062425 this_sequence A007777 A082379 A094589
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KEYWORD
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nonn
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AUTHOR
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Steve Butler (sbutler(AT)math.ucsd.edu), Jul 26 2006
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