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A326025
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Number of maximal subsets of {1..n} containing no sums or products of distinct elements.
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4
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1, 1, 2, 2, 2, 4, 5, 10, 13, 20, 28, 40, 54, 82, 120, 172, 244, 347, 471, 651, 874, 1198, 1635, 2210, 2867, 3895, 5234, 6889, 9019, 11919, 15629, 20460, 26254, 33827, 43881, 56367, 71841, 91834, 117695, 148503, 188039, 311442, 390859, 488327, 610685, 759665
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OFFSET
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0,3
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LINKS
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EXAMPLE
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The a(1) = 1 through a(8) = 13 maximal subsets:
{1} {1} {1} {1} {1} {1} {1} {1}
{2} {2,3} {2,3,4} {2,3,4} {2,3,4} {2,3,4} {2,3,4}
{2,4,5} {2,4,5} {2,3,7} {2,4,5}
{3,4,5} {2,5,6} {2,4,5} {2,4,7}
{3,4,5,6} {2,4,7} {2,5,6}
{2,5,6} {2,5,8}
{2,6,7} {2,6,7}
{3,4,5,6} {2,3,7,8}
{3,5,6,7} {3,4,5,6}
{4,5,6,7} {3,4,6,8}
{3,5,6,7}
{3,6,7,8}
{4,5,6,7,8}
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MATHEMATICA
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fasmax[y_]:=Complement[y, Union@@(Most[Subsets[#]]&/@y)];
Table[Length[fasmax[Select[Subsets[Range[n]], Intersection[#, Union[Plus@@@Subsets[#, {2, n}], Times@@@Subsets[#, {2, n}]]]=={}&]]], {n, 0, 10}]
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PROG
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(PARI) \\ See link for program file.
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CROSSREFS
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Maximal subsets without sums of distinct elements are A326498.
Maximal subsets without products of distinct elements are A325710.
Subsets without sums or products of distinct elements are A326024.
Subsets with sums (and products) are A326083.
Maximal sum-free and product-free subsets are A326497.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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