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# Easy math problem- \$20 frih

Xcelerate
A cool problem someone created:

Find the sum of the elements in the set of integers whose divisors total 256.
TeenZine
haha im not doing your math homework
Xcelerate
It's not math homework.

I enjoy doing math contest style problems. In fact, this problem is straight from http://www.artofproblemsolving.com/Forum/index.php.
janhasdogspot
This was supposed to be easy? How did u start?
jobu
I have a policy on math problems on the internet. If I cant google it, I dont try:) tough question dont forget to explain it to us.
Blaster
101 and 110?
mikethm
 janhasdogspot wrote: This was supposed to be easy? How did u start?

Trust me it is really easy... provided that you think in the right direction... divisors = factors.
ninjakannon
Well, I used the prime factors of 256. Those being 8 twos: 2, 2, 2, 2, 2, 2, 2, 2 or 2^8. Add those up and you get 16.

Am I right?
toughtrio
If you could just elaborate the question a bit, it'd be really very helpfull.
I cant understand, whose divisors add up to 256, and could u tell me how many numbers are actually there.

Warm Regards,
ninjakannon
Does anyone else get the feeling that Xcelerate has abandoned this topic? Perhaps we shall never hear the last of it, and I wanted to know what the answer was too. Darn it!

Anyone think I should I PM Xcelerate?
awesty
I know this is a bit off topic, but what does the '^' mean? I see it everywhere!
ninjakannon
 awesty wrote: I know this is a bit off topic, but what does the '^' mean? I see it everywhere!

The '^' symbol means 'to the power of'.

So 2^3 = 8 because that's the same as 2*2*2.

Do you understand now?
awesty
lol, thanks. I know what to the power of means, I just never knew that ^ meant it >_< lol
ninjakannon
 awesty wrote: lol, thanks. I know what to the power of means, I just never knew that ^ meant it >_< lol

Yeah, I just thought I'd give a full explanation; perhaps someone else won't know (although most people will) and they'll learn a bit more.

Now, have we got an answer to this maths question then?
llobo1
yeah I agree with ninjakannon.
 ninjakannon wrote: Well, I used the prime factors of 256. Those being 8 twos: 2, 2, 2, 2, 2, 2, 2, 2 or 2^8. Add those up and you get 16.

I think this should be the right answer: 16. Unless ...

 Xcelerate wrote: Find the sum of the elements in the set of integers whose divisors total 256.

... does "elements" make reference to scientific elements?? In which case would their be another answer?
ninjakannon
 llobo1 wrote: ... does "elements" make reference to scientific elements?? In which case would their be another answer?

I wouldn't have thought so, llobo1. Why would that reference to scientific elements when - as far as I can see - that has nothing to do with it.

So I still think I'm right. I'm glad you worked that out the same as I did; it backs me up a bit (and I won't look so unintelligent if I get the answer totally wrong).
Xcelerate
I'm sorry about that. I forgot this was here!

Here's the topic on AOPS where the problem is solved:

http://www.artofproblemsolving.com/Forum/viewtopic.php?p=670902

It's really quite an interesting forum. You can learn quite a bit about math. (Anyone taking the AMC tomorrow?)
gh0strec0n_legit
Holy shit that stuff confused the crap out of me
ninjakannon
Wow, that's not so easy as I thought it would be. I guess it would be okay if I knew how to do it in the first place, but not without that knowledge.

I'm not surprised no one got the right answer here.