ref: 5c180cfa6fee3409d60d959adacc0701d16c0e26
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Sixteen <p> Slide the grid squares around so that the numbers end up in consecutive order from the top left corner. <p> Click on the arrows at the edges of the grid to move a row or column left, right, up or down. The square that falls off the end of the row comes back on the other end.