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A167211
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Numbers n such that number of perfect partitions of n-1 divides n.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 11, 13, 15, 16, 17, 19, 21, 23, 29, 31, 32, 33, 37, 39, 40, 41, 43, 47, 48, 51, 53, 57, 59, 61, 64, 67, 69, 71, 73, 78, 79, 83, 87, 89, 93, 97, 101, 103, 107, 109, 111, 113, 123, 127, 128, 129, 130, 131, 132, 137, 139, 141, 149, 151, 157
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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f[1] = 1; f[n_] := f[n] = DivisorSum[n, f[#] &, # < n &]; Select[Range[100], Divisible[#, f[#]] &] (* Amiram Eldar, Dec 30 2019 *)
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CROSSREFS
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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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