MySql conta duplicatas na coluna de uma tabela

$query = "select telco_prov, count(*) c from telco group by telco_prov having c > 1";
$result = mysql_query($query) or die('Error: '.mysql_error ());
while($row = $mysql_fetch_assoc($result)) {
    echo $row['telco_prov'].": <font color= 'red'>".$row['c']."</font>";
}