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A229335
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Sum of sums of elements of subsets of divisors of n.
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10
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1, 6, 8, 28, 12, 96, 16, 120, 52, 144, 24, 896, 28, 192, 192, 496, 36, 1248, 40, 1344, 256, 288, 48, 7680, 124, 336, 320, 1792, 60, 9216, 64, 2016, 384, 432, 384, 23296, 76, 480, 448, 11520, 84, 12288, 88, 2688, 2496, 576, 96, 63488, 228, 2976, 576, 3136, 108
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OFFSET
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1,2
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COMMENTS
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Number of nonempty subsets of divisors of n = A100587(n).
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LINKS
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FORMULA
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a(2^n) = (2^(n+1) - 1) * 2^n.
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EXAMPLE
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For n = 2^2 = 4; divisors of 4: {1, 2, 4}; nonempty subsets of divisors of n: {1}, {2}, {4}, {1, 2}, {1, 4}, {2, 4}, {1, 2, 4}; sum of sums of elements of subsets = 1 + 2 + 4 + 3 + 5 + 6 + 7 = 28 = (2^3-1) * 2^2 = 7 * 4.
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MAPLE
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end proc:
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MATHEMATICA
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Table[Total[Flatten[Subsets[Divisors[n]]]], {n, 100}] (* T. D. Noe, Sep 21 2013 *)
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CROSSREFS
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Cf. A229336 (product of sums of elements of subsets of divisors of n).
Cf. A229337 (sum of products of elements of subsets of divisors of n).
Cf. A229338 (product of products of elements of subsets of divisors of n).
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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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