Generate a function from a list of numbers

[chipChocolate]

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

 

[micromass]

Hint: Look and say

Hint 2: 11 should not be seen as "eleven" but rather as individual ones.

 

[pasmith]

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 $n$th term, given the values of previous terms? If so, you need to do that.

 

[chipChocolate]

The actual question is to find the length of the 31st term.

 

[micromass]

The actual question is to find the length of the 31st term.

You need to recognize the pattern first. See Post #2.

 

[xiavatar]

Hint: The next term says something, quite literally, about the previous term.

 

[chipChocolate]

You need to recognize the pattern first. See Post #2.

Thanks for the hint, I finally got it.

 

[HakimPhilo]

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.