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%I #22 Apr 13 2024 15:02:41
%S 1,6,7,15,18,19,22,174,427,484,1702,2380,6048,8257
%N Numbers k such that (89 + 10^(2*k+1))/99 is prime.
%e 6 is a term because (1/99)*(89 + 10^(2*6+1)) = 101010101011, a prime.
%o (PARI) is(n)=isprime((89+10^(2*n+1))/99) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn
%O 1,2
%A _Jason Earls_, Aug 19 2003
%E a(9)-a(10) from _David Wasserman_, Feb 03 2005
%E a(11)-a(12) from _L. Joris Perrenet_
%E a(13)-a(14) from _Michael S. Branicky_, Apr 12 2024