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%I #18 Jan 17 2019 13:44:08
%S 2,3,6,33,48,74,231,3206,4544,7064,13634,41384,64862,82790
%N Numbers n such that 10^n - 47 is prime.
%C The next term, if one exists, is >100000. - _Robert Price_, Apr 25 2011
%C See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99953".
%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 - 47 = 953 is a prime number.
%t m=1000; For[n=1, n<m, If[PrimeQ[10^n-47], Print[n]];n++ ]
%o (PARI) is(n)=ispseudoprime(10^n-47) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A108330, A108328.
%K more,nonn
%O 1,1
%A _Robert Price_, Dec 17 2010
%E a(12:14)=41384,64862,82790 from _Robert Price_, Apr 25 2011
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