a(n) = smallest prime factor of n-th Lucas number A000032(n), or 1 if there are none.

Terms

a(0) =2a(1) =1a(2) =3a(3) =2a(4) =7a(5) =11a(6) =2a(7) =29a(8) =47a(9) =2a(10) =3a(11) =199a(12) =2a(13) =521a(14) =3a(15) =2a(16) =2207a(17) =3571a(18) =2a(19) =9349a(20) =7a(21) =2a(22) =3a(23) =139a(24) =2a(25) =11a(26) =3a(27) =2a(28) =7a(29) =59