Least prime p such that p+2n is also prime.

Terms

a(0) =2a(1) =3a(2) =3a(3) =5a(4) =3a(5) =3a(6) =5a(7) =3a(8) =3a(9) =5a(10) =3a(11) =7a(12) =5a(13) =3a(14) =3a(15) =7a(16) =5a(17) =3a(18) =5a(19) =3a(20) =3a(21) =5a(22) =3a(23) =7a(24) =5a(25) =3a(26) =7a(27) =5a(28) =3a(29) =3