By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.

What is the 10,001st prime number?

**Script**

Execution Time: 1.3918 seconds

function isPrime($n) { $m = floor(sqrt($n)); for ($x=2; $x<=$m; $x++) { if ($n%$x == 0) { return false; } } return true; } $n = 3; $k = 2; $kMax = 10001; while ($k <= $kMax) { if (isPrime($n)) { if ($k == $kMax) { echo $n.PHP_EOL; break; } $k++; } $n=$n+2; }