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%I #5 Jul 14 2012 11:32:21
%S 3,41,1607,32441,557729,8265137,115438691,1523976761,19358094101,
%T 239211161009,2891512532927,34338035342339,401888325140039,
%U 4646528385435887
%N The 10^n-th twin prime, A001097(10^n).
%C Since A001097(2)=5 is the only number to be member of two twin prime pairs, all terms of this sequence are lower twin primes A001359(k), k = 1,6,51,501,5001,..., cf. the given formula.
%F a(n) = A001359([10^n/2]+1)
%Y Cf. A146214.
%K more,nonn
%O 0,1
%A _M. F. Hasler_, Dec 06 2008
%E a(6)-a(13) from _Donovan Johnson_, Dec 18 2009