To give an even simpler example than above, consider a one-dimensional tiling "T" of the line that looks like where "a" represents an interval of length one, "b" represents an interval of length two. Thus the tiling "T" consists of infinitely many copies of "a" and one copy of "b" (with centre 0, say). Now all translates of "T" are the tilings with one "b" somewhere and "a"s else. The sequence of tilings where "b" is centred at formula_6 converges – in the local topology – to the periodic tiling consisting of "a"s only. Thus "T" is not an aperiodic tiling, since its hull contains the periodic tiling