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A053212
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Number of divisors of the minimal numbers (A007416).
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6
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1, 2, 3, 4, 6, 5, 8, 9, 10, 12, 7, 16, 15, 18, 14, 20, 24, 21, 30, 32, 27, 28, 11, 36, 25, 40, 48, 42, 22, 45, 13, 60, 35, 54, 50, 56, 64, 33, 72, 26, 63, 80, 44, 84, 90, 70, 96, 75, 39, 81, 100, 66, 49, 108, 120, 112, 52, 17, 55, 128, 126, 88, 144, 105, 160
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OFFSET
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1,2
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COMMENTS
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A permutation of the natural numbers.
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LINKS
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FORMULA
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MATHEMATICA
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Reap[For[n = 1, n <= 10^5, n++, tau = DivisorSigma[0, n]; If[Abs[Product[DivisorSigma[0, k] - tau, {k, 1, n - 1}]] > 0, Print[tau]; Sow[tau]]]][[2, 1]] (* Jean-François Alcover, Jan 16 2013 *)
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PROG
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(Haskell)
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CROSSREFS
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KEYWORD
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nonn,nice
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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