images = new Array(6);

images[0] = "<img src='images/v_01.jpg'>";

images[1] = "<img src='images/v_02.jpg'>";

images[2] = "<img src='images/v_03.jpg'>";

images[3] = "<img src='images/v_04.jpg'>";

images[4] = "<img src='images/v_05.jpg'>";

images[5] = "<img src='images/v_06.jpg'>";

images[6] = "<img src='images/v_07.jpg'>";

index = Math.floor(Math.random() * images.length);

document.write(images[index]);