$firtMonday = strtotime("2 January 2012");
$nMonday = $firstMonday + (($week -1) * 7 * 24 * 3600);
echo 'Monday: '. date('Y-m-d', $firstMonday) ."\n";
echo 'Thuesday: '. date('Y-m-d', $firstMonday + 86400) ."\n";
echo 'Wednesday: '. date('Y-m-d', $firstMonday + 2 * 86400) ."\n";
echo 'Thursday: '. date('Y-m-d', $firstMonday + 3 * 86400) ."\n";
echo 'Friday: '. date('Y-m-d', $firstMonday + 4 * 86400) ."\n";
echo 'Suturday: '. date('Y-m-d', $firstMonday + 5 * 86400) ."\n";
echo 'Sunday: '. date('Y-m-d', $firstMonday + 6 * 86400) ."\n";