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%I #15 Nov 20 2018 08:04:56
%S 9,36,192,144,288,1536,576,4608,3840,4608,3072,12288,1152,9216,
%T 1572864,73728,2304,245760,144,73728,4718592,49152,2304,6291456,
%U 294912,18432,589824,294912,18432,100663296
%N a(n) is the number of divisors of the concatenation of 1089 with itself n times.
%C 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.
%e a(2) = tau(10891089) = 36.
%t k = 0; Do[k = 10^4 * k + 1089; Print[DivisorSigma[0, k]], {n, 1, 30}] (* _Ryan Propper_, Oct 15 2005 *)
%Y Cf. A110751, A110753.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Aug 11 2005
%E a(19)-a(30) from _Ryan Propper_, Oct 15 2005
%E Name edited by _Jon E. Schoenfield_, Nov 19 2018
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