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Search: id:A110752
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| A110752 |
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a(n) = Tau(N), where N = the number obtained as a concatenation of 1089 with itself n times. Tau(n) = number of divisors of n. |
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+0
4
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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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COMMENT
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1089 has the property that any number of concatenation of it with self and the digit reversal have same prime divisors.
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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}] (Propper)
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CROSSREFS
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Cf. A110751, A110753.
Sequence in context: A034557 A002063 A075674 this_sequence A094973 A038780 A073984
Adjacent sequences: A110749 A110750 A110751 this_sequence A110753 A110754 A110755
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 11 2005
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EXTENSIONS
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More terms from Ryan Propper (rpropper(AT)stanford.edu), Oct 15 2005
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