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%I #18 Jun 13 2017 10:19:33
%S 2,6,8,17,22,39,89,143,167,312,334,357,414,2254,2694,24094,42081,78632
%N Numbers k such that 10^k + 81 is prime.
%C The next term, if one exists, is >100000. - _Robert Price_, Apr 25 2011
%e 10^2+81=100+81=181 is prime
%t Select[10^Range[25000] + 81, PrimeQ] (* _Alonso del Arte_, Dec 27 2010 *)
%o (PARI) is(n)=ispseudoprime(10^n+81) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 06 2008
%E Added three terms: 2254,2694,24094. _Robert Price_, Oct 09 2010
%E a(17)=42081 from _Robert Price_, Dec 27 2010
%E a(18)=78632 from _Robert Price_, Mar 03 2011