Update
From this by @azerbajdzan, which introduced me to SubstitutionSystem
SubstitutionSystem[{n_ :> n+1}, {1,0}, 8]//Flatten
(* {1,0,2,1,3,2,4,3,5,4,6,5,7,6,8,7,9,8} *)
Original Answer
Flatten@NestList[#+1&,{1,0},8]
{1, 0, 2, 1, 3, 2, 4, 3, 5, 4, 6, 5, 7, 6, 8, 7, 9, 8}
In addition
Array[{#,#-1}&,9,1,Join]
and
Array[{#+1,#}&, 9,0,Join]==Array[{#,#-1}&, 9,1,Join]
Original Post
NestList[#+{1,1}&, {1,0},8]//Flatten