$md5_sql = mysql_escape_string(pack("H32", $md5));
$sql = "SELECT math_outputhash,math_html_conservativeness,math_html,math_mathml FROM math WHERE math_inputhash = '".$md5_sql."'";
$md5_sql = mysql_escape_string(pack("H32", $md5));
$sql = "SELECT math_outputhash,math_html_conservativeness,math_html,math_mathml FROM math WHERE math_inputhash = '".$md5_sql."'";