I am going back into the archive of 10 years of SlideMagic, Ideatransplant, Sticky Slides, Slides that Stick to rescue those slide concepts I discussed and put them in the SlideMagic store. Today's catch is the 15 puzzle that cannot be solved because of some roadblock. Here is the original post from 2009, and below is the slide, ready for download in the SlideMagic store.
Image of a Magic Square in the Sagrada Familia by Alexander Baxevanis on Flickr
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