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%I #28 Jan 17 2019 13:44:08
%S 3,11,17,23,35,161,765,3473,6887,27681,34313
%N Integers n such that 10^n - 23 is a prime number.
%C No additional terms < 40000. - _Robert Price_, Dec 13 2010
%C See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99977".
%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 = 3 is a member because 10^3 - 23 = 1000 - 23 = 977, which is prime.
%t lst={};Do[If[PrimeQ[10^n-23], AppendTo[lst, n]], {n, 0, 10^4}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 19 2008 *)
%Y Cf. A089675, A095714, A092767.
%K more,nonn
%O 1,1
%A Julien Peter Benney (jpbenney(AT)ftml.net), Jun 30 2005
%E a(9)-a(11) from _Robert Price_, Dec 13 2010
%E Edited by _Ray Chandler_, Dec 23 2010