Unable to locate element no such element

[gahhon]

<td> 
    <div class="input-icon">
        <i class="fa fa-user"></i>
        <script type="text/javascript">
            if (getQueryStringParameter("Back") == 1) {                        
                document.write("<input class='form-control placeholder-no-fix' type='text' autocomplete='off' placeholder='User ID' name='tempusername' id='username' autocomplete='off' size='14' maxlength='12' value='' /> <input type='hidden' name='username'>");
            } else {
                document.write("<input class='form-control placeholder-no-fix' type='text' autocomplete='off' placeholder='User ID' name='tempusername'  autocomplete='off' size='14' maxlength='12' value='' /><input type='hidden' name='username'>");
            }
        </script>
        <input class="form-control placeholder-no-fix" type="text" autocomplete="off" placeholder="User ID" name="tempusername" size="14" maxlength="12" value=""><input type="hidden" name="username">
    </div>
 </td>

time.sleep(5)
driver.find_element_by_name('//*[@id="LoginId"]/table/tbody/tr[3]/td/div/input[1]').send_keys("username1")

I did tried wait 20 seconds which is more than enough to let the page finish loaded.
But the result still same. I also tried get the element by name but result the same tho.
Please advise.