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A326178
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Number of subsets of {1..n} whose product is equal to their sum.
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6
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0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67
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OFFSET
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0,3
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COMMENTS
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Same as A001477 (the nonnegative integers) with 3 removed.
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LINKS
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EXAMPLE
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The a(1) = 1 through a(9) = 10 subsets:
{1} {1} {1} {1} {1} {1} {1} {1} {1}
{2} {2} {2} {2} {2} {2} {2} {2}
{3} {3} {3} {3} {3} {3} {3}
{1,2,3} {4} {4} {4} {4} {4} {4}
{1,2,3} {5} {5} {5} {5} {5}
{1,2,3} {6} {6} {6} {6}
{1,2,3} {7} {7} {7}
{1,2,3} {8} {8}
{1,2,3} {9}
{1,2,3}
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MATHEMATICA
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Table[Length[Select[Subsets[Range[n]], Times@@#==Plus@@#&]], {n, 0, 10}]
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CROSSREFS
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KEYWORD
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nonn,dumb
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AUTHOR
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STATUS
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approved
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