As for experience per level. Knowing that we start with 1500 needed at level 1 and 16500 at level 51 this formula gives us that:

1500+((100*(LVL-1))+(100*LVL^1.40429))/2

As for experience per mob. This one you guys may be able to improve on. There were several factors to consider: Char Level, Mob Level, Challenge Rating, Party Members, Party Modifier. I used 5 levels of challenge rating (this is how tough the mob is): 1, 1.1, 1.25, 1.3, 1.4. 1 being an average mob with no modifiers and 1.4 being a veteran of battle. The Party Modifier works like this: by yourself = 1, 2 members = 1.15, 3 members = 1.3, anything over 4 = 0.8. The formula looks something like:

ROUND((300*(Mob Level/Char Level)*2^(Challenge Rating*0.5))*Party Modifier.

So for example, if I'm 35 killing a level 35 mob that's a veteran of battle in a party of 3 I would get 630 experience. I level 40 member in my group would get 550 and a level 28 in my group would get 790.

Some of you who play regularly will have a better idea of what actual experience numbers would be but I think the formula above could be tweaked to give us what we want.

Cheers