672604domain: NAppears in sequencesa(1)=1; for n>1, a(n) = 9*a(n-1) + n.at n=6A014832Take the first n numbers written in base 9, concatenate them, then convert from base 9 to base 10.at n=6A048441The first n digits of the juxtaposition of the base 9 numbers converted to decimal.at n=6A055150