$(document).ready(function() {
	 $('li')
	 	.mouseover(function(){
	 		var index = $('li', $(this).parent()).index(this);
	 		$('#center')
	 			.css('background-image', 'url(/images/page'+index+'.jpg)');
		})
	 	.mouseout(function(){
	 		$('#center')
	 			.css('background-image', 'url(/images/slides.jpg)');
	 	})
});