Bonus Attribute Points - What levels do we get them and how many do we get?

[Deathgiver]

Bonus: 3 + 1 + 1 + 1 + 1 + 2 + 1 + 1 + 1 + 1 + 2 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
Level: 10  12  14  16  18  20  22  24  26  28  30  32  34  36  38  40  41  42  43  44  45  46  47  48  49  50

I may be wrong, but I think that may be the pattern?

So no points from 1-9 and 3 at lvl 10. Then 1 point every even level with 2 points for level 20 and 30. Finally 1 point for each lvl 40-50.

The data points at level 20 and 30 that I can confirm contradict this, but I think I have it nailed down to this:

TotalB:3   4   5   6   7   8   9   10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30   
Bonus: 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
Level: 10  12  14  16  18  20  22  24  26  28  30  32  34  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50

Anyone who can confirm or refute this?