A251757 Odd numbers n not congruent to 1 mod 6 and that are not perfect powers such that for all k >= 1 the numbers n*4^k - 1 are composite.

39939, 656709, 762701, 777149, 779619, 790841, 869859, 1106681, 1156299, 1254341, 1320981, 1330319, 1730681, 2251349, 2344211, 2882541, 2924861, 3079469, 3292241, 3419789, 3580901, 3661529, 3781541, 3784439, 3848289, 4358481, 4384979, 4507889, 4524549

Offset: 1

Author

Arkadiusz Wesolowski, Dec 15 2014

Keywords

• nonn

Comments

a(n) is a Riesel number if it is of the form 6*m + 5.

Crossrefs

Cf. A101036, A251057.