%I A046451
%S A046451 4,9,25,39,49,69,119,121,129,159,219,249,259,329,339,403,469,669,679,
%T A046451 1207,1329,1589,1703,2319,2321,2359,2649,2701,3039,3421,3503,3629,3639,
%U A046451 3899,4303,4607,4839,5603,5739,6209,6401,6979,7269,7663,7819,8203,8519
%N A046451 Concatenation of the 2 prime factors of composite a(n) is a palindrome.
%e A046451 E.g. 3899 = 7 * 557 -> 7557 is palindromic.
%Y A046451 Cf. A046447.
%Y A046451 Sequence in context: A046659 A063760 A130448 this_sequence A158142 A158143 
               A082200
%Y A046451 Adjacent sequences: A046448 A046449 A046450 this_sequence A046452 A046453 
               A046454
%K A046451 nonn
%O A046451 0,1
%A A046451 Patrick De Geest (pdg(AT)worldofnumbers.com), Jul 15 1998.