var banner = new Array();

banner[0]='http://i64.servimg.com/u/f64/14/34/65/11/ogc10.png';
banner[1]='http://i64.servimg.com/u/f64/14/34/65/11/ogc210.png';
banner[2]='http://i17.servimg.com/u/f17/14/57/22/67/system10.png';
banner[3]='http://i67.servimg.com/u/f67/14/57/22/67/ogc211.png';
banner[4]='http://i67.servimg.com/u/f67/14/57/22/67/config10.png';
banner[5]='http://i67.servimg.com/u/f67/14/57/22/67/config11.png';
banner[6]='http://www.ogc-soft.com.ar/mio.png';

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

setInterval("document.getElementById('i_logo').src= banner[Math.floor(Math.random()*banner.length)];",20000);