var banner = new Array();

banner.push('https://nsa13.casimages.com/img/2010/02/08/100208015958824057.png');
banner.push('https://nsa15.casimages.com/img/2010/03/30/100330125424966090.png');
banner.push('https://nsa15.casimages.com/img/2010/03/30/100330010151766690.png');
banner.push('https://nsa15.casimages.com/img/2010/03/30/100330055510447997.png');
banner.push('https://nsa14.casimages.com/img/2010/03/31/100331061605437806.png');

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