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%I #22 Apr 03 2023 10:36:12
%S 1,2,10,12,30,48,373,580,619,718,1592,2928,3076,4741,9198,14020
%N Numbers n>0 such that 666*10^n+1 is prime.
%C No other terms below 10^5. [_Arkadiusz Wesolowski_, Dec 23 2011]
%H Chris Caldwell, The Prime Glossary, <a href="https://t5k.org/glossary/xpage/BeastlyPrime.html">Beastly prime</a>
%H G. L. Honaker, Jr. and Chris Caldwell, <a href="https://t5k.org/curios/cpage/21327.html">Prime Curios! 66601</a>
%H R. Ondrejka, <a href="http://www.utm.edu/research/primes/lists/top_ten/">The Top Ten: a Catalogue of Primal Configurations</a> (May 2001), p. 83
%t Select[Range[10^3], PrimeQ[666*10^# + 1] &] (* _Arkadiusz Wesolowski_, Sep 08 2011 *)
%Y Cf. A186086.
%K nonn,base,more
%O 1,2
%A _Arkadiusz Wesolowski_, Feb 24 2011
%E a(16) (discovered on Dec 09 1999, by Nuutti Kuosa) added by _Arkadiusz Wesolowski_, Mar 16 2011