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%I #14 May 18 2024 11:32:02
%S 1,2,3,11,27,43,122,135,218,230,997,1005,1073,1133,1159,1541,2287,
%T 2912,3692,12503,45761,73659,125021
%N Numbers k such that (29*10^k - 113)/3 is prime.
%C For k>1, numbers k such that the digit 9 followed by k-2 occurrences of the digit 6 followed by the digits 29 is prime (see Example section).
%C a(24) > 2*10^5.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr">Factorization of near-repdigit-related numbers</a>.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/prime_difficulty.txt">Search for 96w29</a>.
%e 2 is in this sequence because (29*10^2 - 113)/3 = 929 is prime.
%e Initial terms and associated primes:
%e a(1) = 1, 59;
%e a(2) = 2, 929;
%e a(3) = 3, 9629;
%e a(4) = 11, 966666666629;
%e a(5) = 27, 9666666666666666666666666629; etc.
%t Select[Range[1, 100000], PrimeQ[(29*10^# - 113)/3] &]
%Y Cf. A056654, A268448, A269303, A270339, A270613, A270831, A270890, A270929, A271269.
%K nonn,more,hard
%O 1,2
%A _Robert Price_, Nov 05 2017
%E a(23) from _Robert Price_, Oct 03 2019
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