a(n) = (10^n + 35)/9 for n>0.

Terms

a(0) =5a(1) =15a(2) =115a(3) =1115a(4) =11115a(5) =111115a(6) =1111115a(7) =11111115a(8) =111111115a(9) =1111111115a(10) =11111111115a(11) =111111111115