TY - JOUR
AU1 - Archer, Aaron F.
AB - Aaron F. Archer 1. INTRODUCTION. In the 1870's the impish puzzlemaker Sam Loyd caused quite a stir in the United States, Britain, and Europe with his now-famous 15-puzzle. In its original form, the puzzle consists of fifteen square blocks numĀ bered 1 through 15 but otherwise identical and a square tray large enough to accommodate 16 blocks. The 15 blocks are placed in the tray as shown in Figure 1, with the lower right corner left empty. A legal move consists of sliding a block adjacent to the empty space into the empty space. Thus, from the starting placement, block 12 or 15 may be slid into the empty space. The object of the puzzle is to use a sequence of legal moves to switch the positions of blocks 14 and 15 while returning all other blocks to their original positions. 6 7 8 9 10 11 12 13 14 15 Figure 1. The starting position for the 15-puzzle. The shaded square is left empty. Loyd writes of how he "drove the entire world crazy," and that "A prize of $1,000, offered for the first correct solution to the problem, has never been claimed, although there are thousands of
TI - A Modern Treatment of the 15 Puzzle
JF - The American Mathematical Monthly
DO - 10.1080/00029890.1999.12005124
DA - 1999-11-01
UR - https://www.deepdyve.com/lp/taylor-francis/a-modern-treatment-of-the-15-puzzle-WQ0oL7IpD4
SP - 793
EP - 799
VL - 106
IS - 9
DP - DeepDyve
ER -