Mystic and rotor

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Continuing on the theme of symmetric figures, Ortwin Schenker suggested combining a Mystic (two Spectres) with a rotor: both are non-tilers.  Arnaud Chéritat was the first to respond with a periodic tiling.  He used a motif of three Mystics and one rotor.  Gaps are filled with single rotors:





A cut-down version of Arnaud's motif can be used to create more complex periodic tilings.  The square unit can be of any size and with different arrangements:




There are eight different combinations of the 'chair' tromino:






Any one of these can be assembled to produce a nonperiodic tiling using a substitution rule:






A beautiful flower motif:



This simple motif produces an attractive spiral:





These drawings were created using the latest stable version of Arnaud Chéritat's applet:
https://www.math.univ-toulouse.fr/~cheritat/AppletsDivers/Monotile/generic/v4.3/


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