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A110752
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a(n) is the number of divisors of the concatenation of 1089 with itself n times.
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3
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9, 36, 192, 144, 288, 1536, 576, 4608, 3840, 4608, 3072, 12288, 1152, 9216, 1572864, 73728, 2304, 245760, 144, 73728, 4718592, 49152, 2304, 6291456, 294912, 18432, 589824, 294912, 18432, 100663296
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OFFSET
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1,1
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COMMENTS
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1089 has the property that any number of concatenations of it with itself and its digit reversal have the same set of distinct prime factors.
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LINKS
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EXAMPLE
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a(2) = tau(10891089) = 36.
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MATHEMATICA
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k = 0; Do[k = 10^4 * k + 1089; Print[DivisorSigma[0, k]], {n, 1, 30}] (* Ryan Propper, Oct 15 2005 *)
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CROSSREFS
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KEYWORD
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base,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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