%I #2 Mar 30 2012 17:28:36
%S 3,5,7,3,17,11,23,89,271,457,967,4049,181,8641,7193,2603047,68476319,
%T 335257649,5554901257,31797598073,23369856751,77031318395801969,
%U 3293187233103900007,637758902554659731714245315207
%N Prime subsequence of A077020 (also A001607).
%H G. P. Michon, <a href="http://www.numericana.com/answer/numbers.htm#m">Never Back to -1</a>.
%e a(13)=181 because A077020(26)=181 is the 13th prime value found in that sequence; A001607(26)=-181.
%K nonn
%O 1,1
%A _Gerard P. Michon_, Dec 01 2004