Filter every 3rd item

HTML

<a href="test.php">test1</a>

<a href="test.php">test2</a>

JavaScript

var eventToPrevent = "click",
    selectorToPrevent = "a";

document.addEventListener(eventToPrevent, function (e) {
    if ($(e.target).is(selectorToPrevent)) e.preventDefault();
}, true);