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Sam Loyd's Fifteen

When it appeared in 1879 as The Gem Puzzle, the 15 Puzzle was accompanied by a cryptic instruction: Place the blocks in the box irregularly, then move until in regular order. At the outset, the applet below shows the 15 blocks in the "regular order". Pressing the "Shuffle" button in combination with the "Cheat" button is a modern day substitute for the block placing instruction. Pressing ether one of the buttons or both of them shuffles the numbers in the box. You move the blocks by clicking in the row or column containing the blank field.

<hr> <h3> This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at, download and install Java VM and enjoy the applet. </h3> <hr>


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