a(n) = Sum_{d|n} 9^(d-1).

Terms

a(0) =1a(1) =10a(2) =82a(3) =739a(4) =6562a(5) =59140a(6) =531442a(7) =4783708a(8) =43046803a(9) =387427060a(10) =3486784402a(11) =31381119478a(12) =282429536482