var inc = 0, timer = 600, err = 10;

function animation( ) {
  setTimeout("Ef1()", timer);
}

function Ef1( ) {
    $("#E1").animate({opacity:0.01}, timer).animate({opacity:1.0}, timer);
    setTimeout("Ef3()", timer * 2 + err);
}

function Ef2( ) {
    $("#E3").animate({opacity:0.01}, timer).animate({opacity:1.0}, timer);
    $("#E2").animate({opacity:0.01}, timer).animate({opacity:1.0}, timer);
    $("#E1").animate({opacity:0.01}, timer).animate({opacity:1.0}, timer);
    setTimeout("Ef1()", timer * 2 + err);
}

function Ef3( ) {
    $("#E3").animate({opacity:0.01}, timer).animate({opacity:1.0}, timer);
    setTimeout("Ef2()", timer * 2 + err);
}