Least k such that 4*n*k+1 is a prime.

Terms

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