Smallest prime factor of f(n) = 10^(2*n+1) + (10^n-1)/9.

Terms

a(0) =2a(1) =7a(2) =3a(3) =11a(4) =41a(5) =3a(6) =61a(7) =7a(8) =3a(9) =11a(10) =113a(11) =3a(12) =53a(13) =7a(14) =3a(15) =11a(16) =29a(17) =3a(18) =17a(19) =7a(20) =3a(21) =11a(23) =3a(24) =41a(25) =7a(26) =3a(27) =11a(28) =53a(29) =3a(30) =661