function rdmbnr() {
  var img = new Array();
img[0] = "http://www.moonphase.jp/miyabi/img/conton-01.jpg";
img[1] = "http://www.moonphase.jp/miyabi/img/conton-02.jpg";
img[2] = "http://www.moonphase.jp/miyabi/img/conton-03.jpg";

var sum = Math.floor(Math.random() * img.length);
document.write('<img src="'+ img[sum] + '" border=0 alt="東方混沌符バナー" title="TCG「東方混沌符」">');
}