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Primes that are the concatenation of two 3-digit primes.
1

%I #16 Mar 19 2015 07:21:52

%S 101107,101113,101149,101173,101197,101281,101293,101347,101359,

%T 101383,101419,101449,101467,101503,101599,101641,101653,101701,

%U 101719,101797,101839,101863,101929,101977,103307,103349,103409,103421,103457,103577,103613

%N Primes that are the concatenation of two 3-digit primes.

%C The last term is a(2753)=997991.

%H Zak Seidov, <a href="/A255976/b255976.txt">Table of n, a(n) for n = 1..2753</a>

%t Select[1000 First@ # + Last@ # & /@ Permutations[Select[Range[100, 999], PrimeQ], {2}], PrimeQ] (* _Michael De Vlieger_, Mar 13 2015 *)

%Y A168529 is a subsequence.

%Y Subsequence of A105184.

%K base,fini,full,nonn

%O 1,1

%A _Zak Seidov_, Mar 12 2015