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%I #9 Mar 05 2020 22:29:27
%S 1,3,4,6,12,19,22,25,43,48,52,54,57,63,66,67,70,73,82,84,85,87,111,
%T 132,139,145,150,151,157,159,160,172,175,187,195,201,204,210,211,213,
%U 216,217,223,228,235,238,241,256,258
%N Numbers n such that the string n2323 is prime.
%H Robert Israel, <a href="/A109069/b109069.txt">Table of n, a(n) for n = 1..10000</a>
%e n=1 is in the sequence because n2323 = 12323 is prime.
%e n=87 is in the sequence because n2323 = 872323 is prime.
%p select(t -> isprime(10^4*t+2323),[$1..1000]); # _Robert Israel_, Mar 05 2020
%K nonn,base
%O 1,2
%A _Parthasarathy Nambi_, Aug 17 2005