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%I #8 Jan 17 2019 13:44:09
%S 0,1,3,4,127,144,213,219,228,463,646,846,1308,1402,1419,1594,1806,
%T 3442,4798,9616,10471,11916
%N Numbers k such that (32*10^k + 337)/9 is prime.
%C For k>1, numbers such that the digit 3 followed by k-2 occurrences of the digit 5 followed by the digits 93 is prime (see Example section).
%C a(23) > 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/primedifficulty.txt">Search for 35w93.</a>
%e 3 is in this sequence because (32*10^3 + 337)/9 = 3593 is prime.
%e Initial terms and primes associated:
%e a(1) = 0, 41;
%e a(2) = 1, 73;
%e a(3) = 3, 3593;
%e a(4) = 4; 35593; etc.
%t Select[Range[0, 100000], PrimeQ[(32*10^# + 337)/9] &]
%Y Cf. A056654, A268448, A269303, A270339, A270613, A270831, A270890, A270929, A271269.
%K nonn,more,hard
%O 1,3
%A _Robert Price_, Jul 25 2017
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