Least k such that 2*n*k + 1 is a prime.

Terms

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