while(true){
aleatorio = Math.random();
numero = Math.round(aleatorio * 3);

if (numero == 0){
imagen = "http://img6.imagebanana.com/img/al28uf5p/001DiannaAgron.jpg";
break;}

if (numero == 1){
imagen = "http://img6.imagebanana.com/img/sqrsm6xt/002SelenaGomez.jpg";
break;}

if (numero == 2){
imagen = "http://img6.imagebanana.com/img/02hafjfd/003ArianaGrande.jpg";
break;}

}
document.write('<a href="http://shadowvslight.forumieren.com/" target="_self" ><img src="' + imagen + '" border=0 style="width: 800px; height: 535px"></a>');