a(n) = (10^n + 71)/9.

Terms

a(0) =9a(1) =19a(2) =119a(3) =1119a(4) =11119a(5) =111119a(6) =1111119a(7) =11111119a(8) =111111119a(9) =1111111119a(10) =11111111119a(11) =111111111119