XP per hero level at Heroes of the Storm

Question

How much XP one needs to level up a hero at Heroes of the Storm?

I found the answer here only for 10 first levels:

1 => 2 : 100k
2 => 3 : 100k
3 => 4 : 100k
4 => 5 : 475k
5 => 6 : 475k
6 => 7 : 1,425m
7 => 8 : ~1.5m
8 => 9 : 2.85m 
9 => 10 : 4.75m

but now there are 20 levels. What are values for them?

Answer 1

The Heroes of the Storm wiki matches my experience, which is a further 4,750,000 XP per level, all the way to level 20.