today = new Date();
jran=today.getTime();
var number=5;
var random_number="";
var image="";
var image_ran="";
ia=9301;
ic=49297;
im=233280;
jran=(jran*ia+ic)%im;
random_number=Math.ceil((jran/(im*1.0))*number);

if(random_number==1){
image_ran="index_01.jpg";
}
if(random_number==2){
image_ran="index_02.jpg";
}
if(random_number==3){
image_ran="index_03.jpg";
}
if(random_number==4){
image_ran="index_04.jpg";
}
if(random_number==5){
image_ran="index_05.jpg";
}

document.write('<img src="images/'+image_ran+'" width=350 height=272>');