332150domain: NAppears in sequencesBase-3 digits are, in order, the first n terms of the periodic sequence with initial period 1,2.at n=11A037480Numbers that are repdigits in base 9.at n=45A048334Numbers whose base-9 representation is 555555555......5.at n=6A125962a(n) = A340131(A001006(n)).at n=10A340395