Numbers n such that A034693(n) = 3: 3n + 1 is prime, but neither n + 1 nor 2n + 1.

Terms

a(0) =24a(1) =32a(2) =34a(3) =64a(4) =76a(5) =80a(6) =92a(7) =94a(8) =104a(9) =110a(10) =122a(11) =124a(12) =132a(13) =144a(14) =152a(15) =154a(16) =182a(17) =202a(18) =206a(19) =214a(20) =220a(21) =236a(22) =242a(23) =244a(24) =246a(25) =252a(26) =274a(27) =286a(28) =294a(29) =302