function ChangeSlideshow(n) {
    var arr = getElem('SlideshowIndicatorContainer').getElementsByTagName("div");
    for(var i=1; i < arr.length+1; i++) if(i != n) getElem('SlideshowIndicator'+i).className = 'off';
    getElem('SlideshowIndicator'+n).className = 'on';
}