%I #12 May 07 2015 23:12:07
%S 66741,308481,436029,636921,1259541,1384059,1997589,2038371,2397951,
%T 2473929,2965569,3885579,3999399,4210989,4303311,4693701,4942311,
%U 5067669,5247051,5367729,5643249,5859369,6269871,6385419,6467361,6660261,6826329,7336521,8302269,9026541
%N Odd numbers n divisible by 3 such that for all k >= 1 the numbers n*4^k + 1 are composite.
%Y Subsequence of A251057.
%K nonn
%O 1,1
%A _Arkadiusz Wesolowski_, May 07 2015