now that I've downloaded the link, it appears to be designed to work on PC's but not Macs -- is that right? Too bad, because I have only Macs (and no PC emulator). --Dan Adam wrote: << Here's a PSPACE-complete puzzle game I created, if anyone is interested: . . . You can design your own levels (and upload!), which can be as complex as any linear-bounded automaton (Turing machine with bounded memory). One of my default levels contains a 15-puzzle built into it.

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Sometimes the brain has a mind of its own.