Smallest prime obtained by appending one or more 9's to n, -1 if no such prime exists.

Terms

a(0) =19a(1) =29a(2) =-1a(3) =499a(4) =59a(5) =-1a(6) =79a(7) =89a(8) =-1a(9) =109a(10) =1199999a(11) =-1a(12) =139a(13) =149a(14) =-1a(15) =1699a(16) =179a(17) =-1a(18) =199a(19) =2099a(20) =-1a(21) =229a(22) =239a(23) =-1a(24) =25999a(25) =269a(26) =-1a(27) =289999a(28) =2999a(29) =-1