> k = function(x) {
    x^4 - 8 * x^3 + 16 * x + 1
}

> nlm(k, p = 2)
$minimum
[1] -335.912

$estimate
[1] 5.884481

$gradient
[1] 1.980277e-06

$code
[1] 1

$iterations
[1] 7


> nlm(k, p = -1)
$minimum
[1] -7.316241

$estimate
[1] -0.7687347

$gradient
[1] 3.939959e-06

$code
[1] 1

$iterations
[1] 5