Semiprimes q such that q^2-4 and q^2+4 are also semiprimes.

Terms

a(0) =9a(1) =21a(2) =69a(3) =129a(4) =381a(5) =2271a(6) =3849a(7) =3909a(8) =3921a(9) =5001a(10) =5079a(11) =5169a(12) =5349a(13) =7041a(14) =16251a(15) =18129a(16) =18399a(17) =20481a(18) =22569a(19) =22641a(20) =22719a(21) =22809a(22) =28029a(23) =32259a(24) =35151a(25) =38559a(26) =39021a(27) =39441a(28) =39981a(29) =41079