Pascal's triangle in PHP

gistfile1.php

function pascal_triangle($c, $r)
{
    if ($c == 0 || $c == $r) {
        return 1;
    } else {
        return pascal_triangle($c-1, $r-1) + pascal_triangle($c, $r - 1);
    }
}

echo pascal_triangle(1,3), "\n";