I tried the following:
function submit_form(input_number, input_egn) {
$('input#user_input_number').val(input_number);
$('input#user_input_egn').val(input_egn);
$.ajax({
url: "http://127.0.0.1:8000/games/xs-software/vaucher.html",
method: "POST",
data: {input_n: input_number}
});
$('form:first').submit();
return false;
}

