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%I #13 Feb 09 2020 11:39:19
%S 2,8,19,31,37,64,68,71,79,85,89,94,100,109,128,136,137,148,149,157,
%T 170,178,179,181,184,190,194,211,215,233,241,250,251,269,277,284,290,
%U 293,298,304,310,313,314,316,317,326,331,353,355,367,370,376,386,394,400
%N Numbers k such that the string k123123 is prime.
%C Also numbers k such that 10^6*k+123123 is prime. - _Stefan Steinerberger_, Mar 03 2006
%H Daniel Starodubtsev, <a href="/A109071/b109071.txt">Table of n, a(n) for n = 1..10000</a>
%e If k=2 then k123123 = 2123123 (prime).
%e If k=94 then k123123 = 94123123 (prime).
%t Select[Range[0, 500], PrimeQ[10^6*# + 123123] &] (* _Stefan Steinerberger_, Mar 03 2006 *)
%K nonn,base
%O 1,1
%A _Parthasarathy Nambi_, Aug 17 2005
%E More terms from _Stefan Steinerberger_, Mar 03 2006