var imagesArray=new Array(
"img/index/js/01.jpg","img/index/js/01.jpg",
"img/index/js/03.jpg","img/index/js/02.jpg",
"img/index/js/05.jpg","img/index/js/06.jpg",
"img/index/js/07.gif");
var ransuu = Math.floor(Math.random()*7);
var replaceImages = imagesArray[ransuu];
document.write("<img src =" + replaceImages + " width='571' height='249' border='0' alt='' />");