An
Old Fashioned Game still in Vogue
15
Slide Puzzle: il
gioco del 15 (it), taquin (fr), juego del 15 (sp), 14/15Puzzle (ger), schuifpuzzel (du), 15パズル (jap), Пятнашки (ru), משחק ה15 (he).


The
History of 15 Puzzle 



It
is not clear when the first slide
puzzle was invented (or made).
But it is a known fact that in 1878 Sam
Loyd, America's puzzleexpert, "drove
the whole world crazy" with his newly "discovered" 1415
puzzle (though some accounts state that,
other authorities dispute this fact). Sam
Loyd claimed from 1891 until his death
in 1911 that he invented the puzzle. Actually,
he had nothing to do with the invention
or popularity of the game... This was a
variation on the "15 Puzzle" which
was made and sold by the Embossing Company
from New York about 10 years earlier!
The "15 Puzzle" consists of 15 squares numbered
from 1 to 15 which are placed in a 4x4 box leaving one position out of the 16
empty. The goal is to reposition the squares from a given arbitrary starting
arrangement by sliding them one at a time into the configuration shown above
(for some initial arrangements, this rearrangement is possible, but for others,
it is not).
It
was not surprising that Sam Loyd drove the
whole world crazy by his variation of the
puzzle of 15. The problem that he formulated
was impossible to solve. When you bought
Loyd's 1415 puzzle the empty square was
positioned bottom right. The pieces were
numbered in order from left to right and
from top to bottom; only the pieces numbered
14 and 15 were reversed. You should reorder
the pieces so all the pieces are in the correct
position and the empty place should be positioned
bottom right again. A slide puzzle with square
pieces can only be solved when the number
of exchanges necessary to solve the puzzle
is even.
A
nice variation of the basic slide puzzle
is a slide puzzle with 15 pieces numbered
form 0 (empty space) to 15 with the instruction
to slide the pieces so that the sum of all
rows and the sum of all columns and the sum
of the diagonals equals 30. Such an ordering
is called a magic square (see example opposite). 
Il gioco
del 15 è un telaietto di
4 caselle x4 all'interno del quale si muovono
tessere scorrevoli numerate. Lo scopo è quello
di mettere in ordine crescente i numeri dall'1
al 15. Questo gioco, secondo Edouard Lucas, è stato
inventato da un sordomuto nel 1870, e si è rapidamente
diffuso negli Stati Uniti e nel mondo intero.
Le applicazioni concrete che risultano dall'abilità nel
risolvere questi generi di puzzle sono: l'ottimizazione dei problemi di magazzinaggio,
parcheggio, circolazione stradale, e così via... 
Le
fameux jeu du 15 ou Taquin
ou PoussePousse, est une petite boîte
ayant 4x4 cases occupées par 15 pièces
carrées numérotées pouvant
glisser et occuper un espace laissé vide.
Le but du jeu étant de remettre en
place les nombres de 1 à 15 en ordre
croissant. Ce jeu a été inventé,
selon Edouard Lucas, par un sourdmuet en
1870, et bénéficia d'une diffusion
mondiale incroyable.
Les applications concretes de la maîtrise du Taquin sont
l'optimisation des problèmes de magasinage, parking, circulation, etc... 




