$("ul > li a")
But you would need to set a class on the root ul if you specifically want to target the outermost ul:
<ul class="rootlist">
...
Then it's:
$("ul.rootlist > li a")....
Another way of making sure you only have the root li elements:
$("ul > li a").not("ul li ul a")
It looks kludgy, but it should do the trick
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