Values of n such that len_x(n) = 0 in A090822.

Terms

a(0) =1a(1) =2a(2) =3a(3) =7a(4) =19a(5) =39a(6) =95a(7) =197a(8) =441a(9) =883a(10) =1771a(11) =3543a(12) =7103a(13) =14213a(14) =28559a(15) =57119