Minimum number of numbers to express every integer below N as a sum

Click For Summary

Homework Help Overview

The discussion revolves around determining the minimum number of distinct values needed to express every integer below a given number N as a sum, particularly in the context of an engineering project involving electric circuits. The problem has a mathematical focus despite its engineering application.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants explore the use of binary values and discuss the implications of using resistors of specific values (1 Ohm, 2 Ohms, 4 Ohms, etc.) to achieve the sums. There is a question regarding the arrangement of these resistors, specifically whether they can only be used in series.

Discussion Status

The discussion is active, with participants offering different perspectives on the arrangement of resistors and the implications for the problem. Some guidance has been provided regarding the use of binary values, and assumptions about the circuit configuration have been clarified.

Contextual Notes

Participants are working under the assumption that the resistors can only be arranged in series, which influences their reasoning about the minimum numbers needed.

CricK0es
Messages
54
Reaction score
3
Homework Statement
I am actually trying to create a load bank that has a range from 0 ohms (no resistors with negligible losses in wires) up to a specified value, N, that increases in value by 1 ohm at each setting to cover all the integers in the range . I want to minimise the number of resistors required for said bank without repetition. I would use python to simulate resistors being switched off and on the path of the current.

Is there some mathematical algorithmn or suggested reading that would help me determine this?
Relevant Equations
*
I have found code to find simply the minimum numbers needed, but I need to do it without repetition given the nature of an electric circuit. I hope that is a sufficient enough explanation of the problem. Despite being an engineering project this aspect is more mathematical.
 
Physics news on Phys.org
just use binary values
 
  • Like
Likes   Reactions: etotheipi, CricK0es and FactChecker
I had the same thought as @phinds . So you need 1 Ohm, 2 Ohms, 4 Ohms, 8 Ohms, ... I don't think you can reduce the number of resistors to less than this.
 
  • Like
Likes   Reactions: FactChecker
Binary is certainly right if they can only be arranged in series, but is that the case here?
 
  • Like
Likes   Reactions: etotheipi and Delta2
Yes they are assumed to only be in series with relays that will ON/OFF as the test cycle is performed. Thank you all!
 

Similar threads

  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 80 ·
3
Replies
80
Views
10K
  • · Replies 7 ·
Replies
7
Views
3K
Replies
3
Views
2K
Replies
2
Views
4K
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K