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%I #32 Jan 17 2019 13:44:08
%S 1,3,5,7,10,11,17,59,81,108,574,629,1069,1759,2063,2682,9174,40929,
%T 42457,66033
%N Integers n such that 10^n+19 is a prime number.
%C Verified terms through 9174. - _Robert Price_, May 24 2010
%C See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10019".
%C No other terms <= 100,000. - _Robert Price_, Mar 03 2011
%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 n = 7 we have 10^7+19 = 10000000+19 = 10000019, which is prime.
%t Select[Range[2*10^3],PrimeQ[10^#+19]&] - _Vladimir Joseph Stephan Orlovsky_, Apr 29 2008
%o (PARI) is(n)=ispseudoprime(10^n+19) \\ _Charles R Greathouse IV_, Apr 28 2015
%Y Cf. A049054, A088274, A088275, A095688.
%K more,nonn
%O 1,2
%A Julien Peter Benney (jpbenney(AT)ftml.net), Jun 01 2005
%E a(17)=9174 from _Ryan Propper_, Jan 02 2008
%E Edited by _Ray Chandler_, Dec 23 2010
%E a(18)=40929 and a(19)=42457 from _Robert Price_, Dec 27 2010
%E a(20)=66033 from _Robert Price_, Jan 09 2011
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