<script type="text/javascript">
        window.history.forward();
        function noBack() { window.history.forward(); }
</script>
   





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 <script type="text/javascript">
        function noBack() {
            window.history.forward()
        }
        noBack();
        window.onload = noBack;
        window.onpageshow = function(evt) { if (evt.persisted) noBack() }
        window.onunload = function() { void (0) }
    </script>


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   <script type = "text/javascript" >

        function preventBack() { window.history.forward(); }

        setTimeout("preventBack()", 0);

        window.onunload = function() { null };

</script>