var imglist = new Array(
      "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo01.jpg",
      "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo02.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo03.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo04.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo05.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo06.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo07.jpg",
	  "http://www.city.omitama.lg.jp/eng/images/eng_sub_head_photo08.jpg"
      );
   var selectnum = Math.floor((Math.random() * 100)) % imglist.length;
   var output = "<img src=" + imglist[selectnum] + ">";
   document.write(output);