- print_r: documentation ( source)
- array_merge: documentation ( source)
- sqrt: documentation ( source)
<?php
function prime($n) {
$s = sqrt($n);
for ($i = 2; $i <= $s; $i++) {
if ($n % $i == 0) {
return array_merge(prime($n/$i), array($i));
}
}
return array($n);
}
$prime = prime(42);
print_r($prime);
?>