:Z-hexomino The following hexomino. The Z-hexomino features in the pentoad, and also in Achim's p144.
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:Z-pentomino Conway's name for the following pentomino, which rapidly dies.
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:zweiback (p30) An oscillator in which two HW volcanoes hassle a loaf. This was found by Mark Niemiec in February 1995 and is too big to show here.