func factorial(_ n: Int) -> Int {
    if n < 2 {
        return 1
    }
    return n * factorial(n - 1)
}
var factarray: [Int] = []
for i in 3 ... 18 {
    factarray.append(factorial(i))
}
var sum = 0
var n = 0
func pow(_ a : Int, _ b : Int) -> Int {
    var t = 1
    for _ in 1 ... b {
        t *= a
    }
    return t
}
while !factarray.contains(sum) {
    n += 1
    for i in 1 ... n {
        sum += pow(i,n)
    }
}