A111981 Numbers n such that 2n-1 and 2n+3 are consecutive primes.

4, 7, 10, 19, 22, 34, 40, 49, 52, 55, 64, 82, 97, 112, 115, 139, 154, 157, 175, 190, 199, 220, 229, 232, 244, 250, 307, 322, 337, 370, 379, 385, 412, 427, 430, 439, 442, 454, 469, 484, 505, 544, 547, 607, 640, 649, 652, 712, 715, 724, 742, 745, 775, 784, 790

Offset: 1

Author

Ray Chandler, Aug 24 2005

Keywords

• nonn

Crossrefs

Essentially the same as A088762.

Formula

a(n) = (A029708(n)-1)/2 = (A029710(n)+1)/2 = (A031505(n)-3)/2.