[Nexus]

(function request(num) {
    var xhr = new XMLHttpRequest();
    xhr.open('POST', '/request-handler/', true);
    xhr.onreadystatechange = function() {
        if (xhr.readyState == 4 && xhr.status == 200)
            request(++num);
    };
    xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    xhr.send('number=' + num);
})(1);