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%I #19 Jun 21 2023 17:18:54
%S 2,3,4,5,6,7,11,57,61,70,127,223,237,240,310,467,651,1935,2333,3457,
%T 4456,6048,11289,12150,24693,28437,31123,32909,52041,58225,68297,
%U 201801
%N Numbers n such that 10^n - 93 is prime.
%C a(33) > 3*10^5.
%C See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99907" or "9w07".
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/">List of near-repdigit-related prime numbers</a>.
%H <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>.
%e 10^3 - 93 = 907 which is a prime number.
%t m=1000; For[n=1, n<m, If[PrimeQ[10^n-93], Print[n]]; n++ ]
%o (PARI) is(n)=ispseudoprime(10^n-93) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A108330, A108328.
%K more,nonn
%O 1,1
%A _Robert Price_, Dec 23 2010
%E a(29-31) from _Robert Price_, May 29 2011
%E a(32) from _Robert Price_, Jun 21 2023
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