Do stacks on Mejai's Soulstealer round up or down on death?

Solution 1:

Did some experimentation and here is what I found: It seems like every stack count but 20 rounds based on the decimal. When I died with 20 stacks, it rounded to 14 stacks instead of 13.

20 stacks goes to 14 stacks. 20 * (2/3) => 13.333 this result rounds up on death, I'm not sure why so I thoroughly tested the other numbers

19 stacks goes to 13 stacks. 19 * (2/3) => 12.6667 rounds to 13.

18 stacks goes to 12 stacks. 20 * (2/3) => 12

17 stacks to 11 stacks. 17 * (2/3) => 11.333 rounds to 11.

15 stacks to 10 stacks. 15 * (2/3) => 10

14 stacks goes to 9 stacks. 14 * (2/3) => 9.333 rounds to 9.

10 stacks goes to 7 stacks. 10 * (2/3) => 6.66667 rounds to 7.

8 Stacks goes to 5 stacks 8 * (2/3) => 5.333333 rounds to 5.

5 Stacks goes to 3 stacks. 5 * (2/3) => 3.3333 rounds to 3.

4 Stacks goes to 3 stacks. 4 * (2/3) => 3.3333 rounds to 3.

3 Stacks goes to 1 stack. 3 * (2/3) => 1

2 Stacks goes to 1 stack. 2 * (2/3) => 1.3333 rounds to 1.

So, besides the odd rounding with 20 stacks, it works as you would expect. I have some other pictures I can insert, but I didn't bother inserting the easily divisible stacks.