Numbers k such that 9*2^k - 1 is prime.

Terms

a(0) =1a(1) =3a(2) =7a(3) =13a(4) =15a(5) =21a(6) =43a(7) =63a(8) =99a(9) =109a(10) =159a(11) =211a(12) =309a(13) =343a(14) =415a(15) =469a(16) =781a(17) =871a(18) =939a(19) =1551a(20) =3115a(21) =3349a(22) =5589a(23) =5815a(24) =5893a(25) =7939a(26) =8007a(27) =11547a(28) =12495a(29) =22555