function makeArray(n) {
this.length = n;
for (var i=1; i<=n; i++) {
this[i] = ""; 
}
return this;
}
var i;
function imagealeatoire() {
i = Math.floor(5 * Math.random() + 1);
return image[i];
}
image = new makeArray(5);
image[1]="images/images_aleatoires/euro_urbain.jpg";
image[2]="images/images_aleatoires/maxi_euro.jpg";
image[3]="images/images_aleatoires/mega_euro.gif";
image[4]="images/images_aleatoires/minieuro.jpg";
image[5]="images/images_aleatoires/euro_medium.jpg";
document.write("<IMG SRC=" +imagealeatoire() +" BORDER=0>");