var banner = new Array();

banner.push('https://img11.hostingpics.net/pics/656029ABV21.png');
banner.push('https://img11.hostingpics.net/pics/198467ABV22.png');
banner.push('https://img11.hostingpics.net/pics/692938ABV23.png');

document.getElementById('i_logo').src= banner[Math.floor(Math.random()*banner.length)];