[jQuery] Cookie Plugin - Trying to get the values of elements in the array of cookies.

I'm using the cookie plugin.  And, I have created 4 cookies with it
and they are named:

Expanded[1]=3
Expanded[2]=18
Expanded[3]=27
Expanded[4]=37

I also keep a count of the number of cookies that have been created
and the name of this cookie is this:

onExpandCount=4


How do I loop through these cookies?  I can't seem to get the syntax
right.

Here's what I've tried:

function expandMenuUsingCookie() {
        for (var index=0;index<$.cookie('onExpandCount');index++) {
                        //console.log(index);
                        
YAHOO.widget.TreeView.getNode('menu',$.cookie('Expanded['+index
+']')).toggle();
                }
}

There's something wrong with this line right about where I try to get
the value of the cookie:
YAHOO.widget.TreeView.getNode('menu',$.cookie('Expanded['+index
+']')).toggle();