In his last wager, the Baron challenged Sir R----- to put a four by four square of tiles, numbered from one to sixteen, into sequential order from top-left to bottom-right by rotating two by two squares of adjacent tiles. That Sir R----- should have had a prize of three coins if he had succeeded and the Baron should have had one of two coins if he had not suggests that the key to reckoning whether Sir R----- should have taken this wager is to figure whether or not every arrangement of the tiles might be arrived at through such manipulations.
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