function random(){

url = new Array(10); 
img = new Array(url.length); 

i = Math.floor(Math.random( ) * url.length);

url[0]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+432376+1JJG+5YRHD";
img[0]="http://www25.a8.net/svt/bgt?aid=080203798247&wid=001&eno=01&mid=s00000007198001002000&mc=1";

url[1]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+526NW2+B4K+2BFH01";
img[1]="http://www20.a8.net/svt/bgt?aid=080203798306&wid=001&eno=01&mid=s00000001442014013000&mc=1";

url[2]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+5SZ642+1A54+ZQ80H";
img[2]="http://www22.a8.net/svt/bgt?aid=080203798351&wid=001&eno=01&mid=s00000005980006001000&mc=1";

url[3]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+5X57CI+XXY+TVYKH";
img[3]="http://www28.a8.net/svt/bgt?aid=080203798358&wid=001&eno=01&mid=s00000004399005020000&mc=1";

url[4]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+6G72PE+REE+5YRHD";
img[4]="http://www25.a8.net/svt/bgt?aid=080203798390&wid=001&eno=01&mid=s00000003551001002000&mc=1";

url[5]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+6NC9YQ+HEE+NU729";
img[5]="http://www29.a8.net/svt/bgt?aid=080203798402&wid=001&eno=01&mid=s00000002255004004000&mc=1";

url[6]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+6VOCFM+Y92+15Q22P";
img[6]="http://www22.a8.net/svt/bgt?aid=080203798416&wid=001&eno=01&mid=s00000004439007008000&mc=1";

url[7]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+786G4Y+X20+5YRHD";
img[7]="http://www22.a8.net/svt/bgt?aid=080203798437&wid=001&eno=01&mid=s00000004284001002000&mc=1";

url[8]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+7E4S6Q+RPS+60WN5";
img[8]="http://www23.a8.net/svt/bgt?aid=080203798447&wid=001&eno=01&mid=s00000003592001012000&mc=1";

url[9]="http://px.a8.net/svt/ejp?a8mat=1BR1NA+7NNPV6+GXG+BWVTD";
img[9]="http://www25.a8.net/svt/bgt?aid=080203798463&wid=001&eno=01&mid=s00000002194002001000&mc=1";

url[10]="http://px.a8.net/svt/ejp?a8mat=1HW8O6+526NW2+1PYK+5YRHD";
img[10]="http://www23.a8.net/svt/bgt?aid=090523878306&wid=001&eno=01&mid=s00000008030001002000&mc=1";

url[11]="http://px.a8.net/svt/ejp?a8mat=1HW8O6+7IW90Y+1O5A+6I9N5";
img[11]="http://www24.a8.net/svt/bgt?aid=090523878455&wid=001&eno=01&mid=s00000007795001093000&mc=1";

/*これ以降は、3,4,5と数字を増やしてください。*/

document.write('<a href="'+url[i]+'" target="_blank">'); 
document.write('<img src="'+img[i]+'" border="0"></a>');

}