Generate a function from a list of numbers

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Homework Help Overview

The discussion revolves around generating a function from a specific list of numbers, identified as a sequence that appears to follow a "look-and-say" pattern. Participants are tasked with determining the 31st term in this sequence and its length.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the nature of the sequence and question how to construct the nth term based on previous terms. There is a focus on recognizing patterns and understanding the implications of truncating the sequence.

Discussion Status

The discussion is active, with hints provided regarding the nature of the sequence. Some participants express the need to identify the pattern before proceeding, while others acknowledge the complexity of the problem, noting that there may be multiple interpretations or answers.

Contextual Notes

Participants mention the importance of recognizing the pattern and the potential for multiple answers, referencing external sources such as OEIS for additional context.

chipChocolate
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I have a list of numbers x = [1, 11, 21, 1211, 111221,...], I need to find the 31st number in that list.
 
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Hint: Look and say

Hint 2: 11 should not be seen as "eleven" but rather as individual ones.
 
chipChocolate said:
I have a list of numbers x = [1, 11, 21, 1211, 111221,...], I need to find the 31st number in that list.

It could be anything. Truncating a sequence loses all information about subsequent terms.

Are you told how to construct the [itex]n[/itex]th term, given the values of previous terms? If so, you need to do that.
 
The actual question is to find the length of the 31st term.
 
Last edited:
chipChocolate said:
The actual question is to find the length of the 31st term.

You need to recognize the pattern first. See Post #2.
 
Hint: The next term says something, quite literally, about the previous term.
 
micromass said:
You need to recognize the pattern first. See Post #2.

Thanks for the hint, I finally got it.
 
The problem with this type of questions is that they have more than one answer in general. For this particular sequence we have 3 possibilities that can be found at OEIS.
 

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