%I #4 Feb 11 2014 19:05:27
%S 2,3,5,6,7,8,9,11,12,13,16,17,18,19,21,22,23,24,25,27,29,31,32,33,36,
%T 37,39,41,43,44,46,47,48,49,51,53,54
%N Numbers n such that the concatenation of the prime factors of n (in increasing order) is prime.
%e The prime factors of 51 are 3 and 17 and their concatenation 317 is prime, so 51 belongs to the sequence.
%K base,easy,nonn
%O 1,1
%A _Joseph L. Pe_, Mar 16 2002
