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A187492
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Number of 5-element nondividing subsets of {1, 2, ..., n}.
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1
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2, 4, 6, 11, 15, 24, 50, 83, 127, 209, 310, 431, 679, 921, 1229, 1624, 2145, 2770, 3752, 4866, 6141, 7753, 9679, 12005, 15027, 18134, 22045, 26368, 31712, 37763, 45569, 53810, 63393, 73560, 86496, 100071, 117234, 134623, 155465, 176876
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OFFSET
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21,1
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COMMENTS
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A set is called nondividing if no element divides the sum of any nonempty subset of the other elements.
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LINKS
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EXAMPLE
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a(21) = 2 because there are two 5-element nondividing subsets of {1,2,...,21}: {12,16,18,19,21}, {12,14,18,20,21}.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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