$(document).ready(function(){
            lastBlock = $("#a1");
            maxWidth = 600;
            minWidth = 75;	
        
            $("ul.accordion li a").hover(
              function(){
                $(lastBlock).animate({width: minWidth+"px"}, { queue:false, duration:400 });
            $(this).animate({width: maxWidth+"px"}, { queue:false, duration:400});
            lastBlock = this;
              }
            );
        });