<?php
function page($page_num) {
    $query = $_GET;
    $query['d'] = $page_num;
    $query_result = http_build_query($query);
    return "<a href='{$_SERVER['PHP_SELF']}?{$query_result}'>Link</a>";
}

for($i = $pagenum+1; $i <= $last; $i++){
$paginationCtrls .= '<a href="'. page($i).'" class="btn btn-default">'.$i.'</a> &nbsp; ';
    if($i >= $pagenum+4){
        break;
    }
}