You have to multiply two numbers to get to the target product, but you're only adding one of them to your list ;-)

Every time you find a divisor you're throwing away the other part of the information ;-)

Why result belongs to the class? The next time your function is called it'll have the previous value, that's why you get expected: 0 but was: 3. Not a kata issue, it's your code that should be fixed. Try calling your function several times in eclipse too, it'll also fail there.

The assertion with 39 is this one: assertEquals(3, Persist.persistence(39)); and it's ok. I've solved it in java and it worked fine for me.