function random_index(){

var nbrpl=2 //nombre de planches editees
var nbrct=9 //nombre de cartes par planche
var nodossier=276 //numero du dossier d'archive

var nbra1=Math.floor(Math.random()*nbrpl)
var nbra2=Math.floor(Math.random()*nbrct)
nbrpl1=nodossier + nbra1
if (nbra2<=9)
{
nbra3="0" + nbra2}
else
{
nbra3=nbra2}
if (nbra2==0)
{
nbra3="01"}

var nbrb1=Math.floor(Math.random()*nbrpl)
var nbrb2=Math.floor(Math.random()*nbrct)
nbrpl2=nodossier + nbrb1
if (nbrb2<=1)
{
nbrb2=2}
if (nbrb2==nbra2)
{
nbrb2=nbra2-1}
if (nbrb2<=9)
{
nbrb3="0" + nbrb2}
else
{
nbrb3=nbrb2}

document.write('<a href=\"cartes/j' + nodossier + '/' + nbrpl1 + nbra3 + '.htm\" title=\"to enter the collection\"><img src=\"cartes/j' + nodossier + '/vignets/' + nbrpl1 + nbra3 + '.jpg\" width=\"120\" height=\"83\" style=\"border-style:none\"></a><p style=\"padding-bottom:5px\"><a href=\"cartes/j' + nodossier + '/' + nbrpl2 + nbrb3 + '.htm\" title=\"to enter the collection\"><img src=\"cartes/j' + nodossier + '/vignets/' + nbrpl2 + nbrb3 + '.jpg\" width=\"120\" height=\"83\" style=\"border-style:none\"></a></p>');
}
random_index()