Sum of power of two exact 2010 different ways

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Homework Help Overview

The discussion revolves around determining all numbers that can be expressed in exactly 2010 different ways as a sum of powers of two, with the condition that each exponent can appear a maximum of three times in any single sum. The original poster expresses confusion about how to approach this problem and provides examples of sums involving powers of two.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants explore the number of ways to express specific powers of two, such as 2^4, and question the coherence between the number of different sums and the powers involved. There is also a discussion about whether the original question pertains to finding numbers that can be expressed in 2010 ways or the number of ways to express the number 2010 itself.

Discussion Status

Some participants have attempted to clarify the problem and provide examples, while others question the relevance of certain responses. There is a mix of interpretations regarding the original question, and no consensus has been reached on a specific approach or solution.

Contextual Notes

Participants note the constraints of the problem, including the maximum appearance of exponents and the counting of sums where only the order of summands is changed. There is also mention of a potential connection to a specific source, which may influence the understanding of the problem.

Christian1992
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Hello,

I look for a solution for the following problen.

Determine all numbers, which can be written in exact 2010 different ways as a sum of powers of two with non-negative exponent, while all exponents are only allowed to appear maximal three times in one sum.
(All sums where only the order of the summands is changed are count as one sum.)


My problem is that I do not have any idea, how to find a solution to this task.
Therefore I started to determine in how many different sums I can write for example 2^4:
1. 2^4
2. 2*2^3
3. 2*2^2+2^3
4. 2*2+2^2+2^3
5. 2*2^0+2+2^2+2^3
6. 2*2^0+3*2+2^3
7. 2*2^0+3*2+2*2^3

Nevertheless, I did not find any coherenz zu the number and the number of different sums.

Do you have any tips?

Christian
 
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No idea?
 
Christian1992 said:
Hello,

I look for a solution for the following problen.

Determine all numbers, which can be written in exact 2010 different ways as a sum of powers of two with non-negative exponent, while all exponents are only allowed to appear maximal three times in one sum.
(All sums where only the order of the summands is changed are count as one sum.)
I don't understand what you're asking. Is it that you want all numbers that can be written in exactly 2010 different ways?

Or is it that you want to find the number of ways that 2010 can be written as a sum of powers of 2?
Christian1992 said:
My problem is that I do not have any idea, how to find a solution to this task.
Therefore I started to determine in how many different sums I can write for example 2^4:
1. 2^4
2. 2*2^3
3. 2*2^2+2^3
4. 2*2+2^2+2^3
5. 2*2^0+2+2^2+2^3
6. 2*2^0+3*2+2^3
7. 2*2^0+3*2+2*2^3

Nevertheless, I did not find any coherenz zu the number and the number of different sums.

Do you have any tips?

Christian
 
Christian1992 said:
Hello,

I look for a solution for the following problen.

Determine all numbers, which can be written in exact 2010 different ways as a sum of powers of two with non-negative exponent, while all exponents are only allowed to appear maximal three times in one sum.
(All sums where only the order of the summands is changed are count as one sum.)


My problem is that I do not have any idea, how to find a solution to this task.
Therefore I started to determine in how many different sums I can write for example 2^4:
1. 2^4
2. 2*2^3
3. 2*2^2+2^3
4. 2*2+2^2+2^3
5. 2*2^0+2+2^2+2^3
6. 2*2^0+3*2+2^3
7. 2*2^0+3*2+2*2^3

Nevertheless, I did not find any coherenz zu the number and the number of different sums.

Do you have any tips?

Christian

Hi there!
I believe you quote the question from Columbus state university .

This is an easy question.
Assume there is four blocks since the two non zero integer are similar ,
we label one of the a and b. one with a selection of 3 integers another with 4.
For a>2.


Therefore the blocks of 4 integer will look like this:
a00b
a0b0
ab00

I'll leave the rest to you.
ans is thirty-_____ .
 
icystrike said:
Hi there!
I believe you quote the question from Columbus state university .

This is an easy question.
Assume there is four blocks since the two non zero integer are similar ,
we label one of the a and b. one with a selection of 3 integers another with 4.
For a>2.


Therefore the blocks of 4 integer will look like this:
a00b
a0b0
ab00

I'll leave the rest to you.
ans is thirty-_____ .

Huh? You're sure this is the answer to the right question?
 
Christian1992 said:
Hello,

I look for a solution for the following problen.

Determine all numbers, which can be written in exact 2010 different ways as a sum of powers of two with non-negative exponent, while all exponents are only allowed to appear maximal three times in one sum.
(All sums where only the order of the summands is changed are count as one sum.)


My problem is that I do not have any idea, how to find a solution to this task.
Therefore I started to determine in how many different sums I can write for example 2^4:
1. 2^4
2. 2*2^3
3. 2*2^2+2^3
4. 2*2+2^2+2^3
5. 2*2^0+2+2^2+2^3
6. 2*2^0+3*2+2^3
7. 2*2^0+3*2+2*2^3

Nevertheless, I did not find any coherenz zu the number and the number of different sums.

there are actually 9 ways to write 2^4

writing them in 'binary'

10000
2000
1200
1120
1112
1032
320 = 3*2^2 + 2 * 2^2
312 = 3*2^2 + 1 * 2^1 + 2*2^0
232 = 2*2^2 + 3 * 2^1 + 2*2^0

you missed the last 3 and your number 7 isn't valid.

It appears that if f(n) is the number of ways to write n, then f(n) = 1 + floor(n/2)

(floor(x) is the greatest integer <= x)

I haven't been able to prove this so far. It's easy to prove that f(2n+1) = f(2n) so you
only have to prove f(n) = 1+n/2 for even numbers.
 

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