# How much food does it take to get a dragon to level 15?

I want to raise some dragons to level 15 as it's the highest level I can reach.

How many treats (total) does it take to get a dragon from level 1 to 15?

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Hooray math time!

Dragons start off at level 1, needing to be fed 5 units of food at a time. Every level after that, the amount of food doubles - level 2 requires 10 food, level 3 requires 20 food, etc. You need to feed a dragon four times before it levels, so we can factor that in and pretend it's already required - a level 1 dragon requires 5 * 4 = 20 units of food to level, a level 2 dragon requires 40, a level 3 dragon requires 80, and so on.

Now, if we factor out 20 units of food from those numbers (it's 5 * 4, which are just constants we've applied), we get a simple pattern: level 1 requires 1, level 2 requires 2, level 3 requires 4, level 4 requires 8, and so on; if we can figure out a quick way to sum that up from level 1 to level 15, (or alternatively, from 2^0 to 2^14) then we just need to multiply everything by 20 and we'll have our answer.

Since we need to take the sum of those things, and we can tell by looking at them that they're powers of two, we stick "sum of powers of 2" into the ALL KNOWING ORACLE. That gives us this result, where someone says that the formula is 2^(N+1)-1 and that this is in fact a geometric series, and then we lose like three hours on Wikipedia but that's okay.

So, now we know that the equation is going to be of the form 20 * (2^(N+1)-1) or maybe it's N-1 or maybe just N, I don't know, I kinda lost track during that Wikipedia binge. Since it's early in the morning and we're not entirely sure we did that right, we'll write down the values that 20 * (2^(N)-1) puts out and see how they match what we know:

``````N: Result
1: 20
2: 60
3: 140
``````

So it looks like if you want to do this calculation for level N, you'd put in N-1, making it 20 * (2^(N-1)-1). Otherwise, the values look good. Yay!

## tl;dr:

It requires 327660 units of food to take a dragon from level 1 to the beginning of level 15, or 655340 units of food to take the dragon to the end of level 15 (a full food bar). In general, you can calculate the amount of food required to take a dragon from level 1 to level N by plugging N into the equation 20 * (2^(N-1)-1).

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Crap, that;s a lot more than I thought it was using! Thought it was around 400,000. Thanks for the formula, that's great! – Ben Brocka Apr 8 '12 at 16:10
NO. It's 327660, you're doing it wrong except for moo cow, he's somewhat right edit: you guys were counting 20 food from nothing to level 15, but you start at level 1 so you only have to level up 14 levels. – user38272 Dec 12 '12 at 9:04
@vertre is correct. – Shadur Dec 21 '12 at 13:11
You have to count the 20 food it takes to get from Level 1 to level 2. You start at Level 1, but with an empty food meter. However, @vertre 's total is correct. I have recalculated and updated my answer. – EBongo Dec 22 '12 at 16:23
Well I did say it was early in the morning when I wrote this... 327660 is the amount to take your dragon to the beginning of level 15, 655340 is the amount to take your dragon to the end of level 15 (or level 16). – Tacroy Dec 23 '12 at 19:48

The amount of treats required per level starts at 20 for level 1 and doubles every level. Per the DragonVale Wiki this means that by level 15 you will require 163,840 treats to go from level 14 to level 15. To your exact question, that means the cumulative total you'll need to go from level 1 to level 15 is 327,660 treats.

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Your math is off by one. It's 327680, not 655340. – Shadur Dec 21 '12 at 13:12
@Shadur Off by one level, thanks for the catch. The treat total is actually 327,660 - I recalculated myself and checked the wiki total cited and they match. This matches my experience (~300k to level 15) - don't know why 600k made sense to me when I wrote this - but that was a long time ago :). – EBongo Dec 22 '12 at 16:19