function MostrarOcultarImagenes () {
for (i=1; i<=numeroimages; i++)
{
eval("document.getElementById('IM"+i+"').style.display = 'none';")
}
document.getElementById("IM1").style.display = 'block';

}
function AbreImagen (numeroimagen) {
MostrarOcultarImagenes ();
document.getElementById(numeroimagen).style.display = 'block';
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}