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%I #22 Jan 17 2019 13:44:08
%S 2,4,6,7,8,14,20,110,138,140,145,300,390,1484,3194,3300,3950,4986,
%T 5574,5630,5874,8866,11390,45130,86110
%N Numbers n such that 10^n - 69 is prime.
%C The next term, if it exists, is > 100000.
%C See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99931".
%H <a href="/A177866/b177866.txt">Table of n, a(n) for n = 1..25</a>
%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 10^6 - 69 = 999931 which is a prime number.
%t m=1000; For[n=1, n<m, If[PrimeQ[10^n-69], Print[n]]; n++ ]
%o (PARI) is(n)=ispseudoprime(10^n-69) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A108330, A108328.
%K more,nonn
%O 1,1
%A _Robert Price_, Dec 28 2010
%E a(24-25)=45130,86110 from _Robert Price_, May 29 2011
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