A107290 Numbers (M_k+2)/3 where M_k is a Mersenne prime > 6.

3, 11, 43, 2731, 43691, 174763, 715827883, 768614336404564651, 206323339880896712483187371, 54086425609737787797192670096043, 56713727820156410577229101238628035243

Offset: 3

Author

Yasutoshi Kohmoto, May 22 2005

Keywords

• nonn

Comments

Many small values are prime; (M_89+2)/3 is the first composite.

Links

• C. K. Caldwell, The Prime Glossary, Bateman, Selfridge, Wagstaff; the New Mersenne Prime Conjecture

Crossrefs

Cf. A000668.

Extensions

Edited by Don Reble, May 23 2005