Numbers k such that 2*k+1, 4*k+1 and 8*k+1 are primes.

Terms

a(0) =9a(1) =39a(2) =165a(3) =219a(4) =249a(5) =309a(6) =414a(7) =534a(8) =639a(9) =765a(10) =1044a(11) =1065a(12) =1089a(13) =1155a(14) =1395a(15) =1509a(16) =1530a(17) =1554a(18) =1590a(19) =1884a(20) =2079a(21) =2115a(22) =2130a(23) =2310a(24) =2319a(25) =2430a(26) =2475a(27) =2709a(28) =2874a(29) =3060