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A187493
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Number of 6-element nondividing subsets of {1, 2, ..., n}.
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1
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1, 3, 4, 7, 15, 27, 45, 55, 85, 133, 199, 262, 378, 534, 803, 999, 1319, 1742, 2309, 3007, 4020, 5166, 6565, 7950, 10380, 12882, 16533, 19664, 24099, 30912, 37550, 44092, 54465, 65117, 79616, 94144, 111780, 132592, 159228, 187506, 219949, 256514
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OFFSET
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31,2
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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(31) = 1 because there is one 6-element nondividing subset of {1,2,...,31}: {16,19,23,24,28,31}.
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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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