$re = '/^\d*(0)1[23456789] | (0|1)2[3456789] | (0|1|2)3[456789] |(0|1|2|3)4[56789] | (0|1|2|3|4)5[6789] | (0|1|2|3|4|5)6[789] |(0|1|2|3|4|5|6)7[89] | (0|1|2|3|4|5|6|7)8(9)\d*$/mx';
$str = '123
9876456000
123456789
246
91370
3456
111
415263
xyz123xyz';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php