47 Ancient Nord arrows and 2 level-ups of Archery.

 Now what you need is the Atherial Crown and put the Ritual Stone power into it. Then, you can resurrect this entire batch of corpses and have them follow you around.
Normally the Stone's power can only be used once a day but since it's in the crown, you can unequip and re-equip the crown over and over, thereby "recharging" the power to reuse unlimited. Also, the Ritual Stone power causes them to flop down onto the ground instead of disintegrating when the timer runs out and you can reuse them over and over. You end up with an undead army that adds its victims to itself, resulting in a massive horde of undead servants.
Best part is the crown is an item you can get legit from a quest from the Dawnguard expansion so it's not a cheat or exploit. 100% Canon. 
Now go be that Necromancer Lord you always wanted to be!

I don't actually expect you to do this, BTW. It just seems a shame to waste all that free cannon fodder.

2 hours ago, vancleef said:

I don't actually expect you to do this, BTW. It just seems a shame to waste all that free cannon fodder.

And I get them all outside, they all crumble in to ash piles and then the cell never loads again because there's 27 piles of smoldering ash eating up my frame rate.  Hard pass. 

Yep.. Bugthesda never gave NPC the ability to jump.

"And I get them all outside, they all crumble in to ash piles and then the cell never loads again because there's 27 piles of smoldering ash eating up my frame rate. "

The Ritual Stone doesn't reduce your "followers" to ash. You can actually reuse them! Then, when they kill a bunch of new victims, you add them to the roster and so on and so on!

That said, there instead would be 107 bodies fucking up your frame rate. So, yeah. Hard pass.