%I A049054
%S A049054 1,2,5,6,11,17,18,39,56,101,105,107,123,413,426,2607,7668,10470,11021,
%T A049054 17753,26927
%N A049054 Numbers n such that 10^n + 3 is prime.
%H A049054 Makoto Kamada, <a href="http://homepage2.nifty.com/m_kamada/math/10003.htm">
               Factorizations of 100...003</a>.
%H A049054 Sabin Tabiraca and Kieran Reynolds, <a href="http://multimedia.ucc.ie/
               Staff/ST/articles/SNJ03_Tabirca1.ps">Lacunary Prime Numbers</a>.
%H A049054 <a href="Sindx_Pri.html#Pri_rep">Index entries for primes involving repunits</
               a>.
%e A049054 5 is a member since 10^5 + 3 = 100003 is a prime.
%e A049054 6 is a member since 10^6 + 3 = 1000003 is a prime.
%t A049054 Do[ If[ PrimeQ[ 10^n + 3], Print[n]], {n, 0, 18000}] (from Robert G. 
               Wilson v Jun 15 2002)
%Y A049054 Sequence in context: A135013 A103035 A088273 this_sequence A135476 A051217 
               A110975
%Y A049054 Adjacent sequences: A049051 A049052 A049053 this_sequence A049055 A049056 
               A049057
%K A049054 more,nonn
%O A049054 1,2
%A A049054 G. L. Honaker, Jr. (honak3r(AT)gmail.com)
%E A049054 More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 15 2002
%E A049054 a(16) from Ray Chandler (rayjchandler(AT)sbcglobal.net), Oct 09 2003
%E A049054 a(17) - a(20) from Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 18 2005
%E A049054 26927 from Jason Earls (zevi_35711(AT)yahoo.com), Jan 01 2008