%I #2 Dec 05 2013 19:56:36
%S 2,5,13,13,31,31,71,73,73,71,199,157,157,211,211,337,199,419
%N a(n) = least prime of the form nk+1 where the sequence of k is a rearrangement of the natural numbers.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Nov 18 2003