%I #4 Apr 03 2023 10:36:10
%S 3,11,43,2731,43691,174763,715827883,768614336404564651,
%T 206323339880896712483187371,54086425609737787797192670096043,
%U 56713727820156410577229101238628035243
%N Numbers (M_k+2)/3 where M_k is a Mersenne prime > 6.
%C Many small values are prime; (M_89+2)/3 is the first composite.
%H C. K. Caldwell, The Prime Glossary, <a href="https://t5k.org/glossary/page.php?sort=NewMersenneConjecture">Bateman, Selfridge, Wagstaff; the New Mersenne Prime Conjecture</a>
%Y Cf. A000668.
%K nonn
%O 3,1
%A _Yasutoshi Kohmoto_, May 22 2005
%E Edited by _Don Reble_, May 23 2005