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 A110752 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. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 1089 has the property that any number of concatenation of it with self and the digit reversal have same prime divisors. LINKS EXAMPLE a(2) =tau(10891089) = 36. MATHEMATICA k = 0; Do[k = 10^4 * k + 1089; Print[DivisorSigma[0, k]], {n, 1, 30}] (Propper) CROSSREFS Cf. A110751, A110753. Sequence in context: A265837 A264359 A280353 * A094973 A038780 A073984 Adjacent sequences:  A110749 A110750 A110751 * A110753 A110754 A110755 KEYWORD base,nonn AUTHOR Amarnath Murthy, Aug 11 2005 EXTENSIONS More terms from Ryan Propper, Oct 15 2005 STATUS approved

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