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%I #11 Sep 08 2022 08:45:16
%S 1,5,7,11,13,17,25,26,29,34,47,49,55,67,77,80,98,101,110,115,118,124,
%T 133,134,136,143,158,169,181,188,193,199,209,211,220,224,227,239,241,
%U 248,250,260,265,266,277,280,293,299,301,302,311,313,320,326,337,340,343,346,364,365,370,371,382,398
%N Numbers k such that k99999 is prime.
%e If k=1, then k99999 = 199999 (prime).
%e If k=34, then k99999 = 3499999 (prime).
%e If k=98, then k99999 = 9899999 (prime).
%o (Magma) [ n: n in [1..700] | IsPrime(Seqint([9,9,9,9,9] cat Intseq(n))) ]; // _Vincenzo Librandi_, Feb 04 2011
%K base,nonn
%O 1,2
%A _Parthasarathy Nambi_, Feb 22 2005