# Look-and-say number generator

## World's simplest math tool

Free online look-and-say number generator. Just specify how many look-and-say numbers you need and you'll automatically get that many numbers. There are no ads, popups or nonsense, just an awesome look-and-say calculator. Press a button, get look-and-say sequence. Created by mathematicians for mathematicians.

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Look-and-say number generator tool
What is a look-and-say number generator?

This tool calculates look-and-say sequence numbers. Look-and-say sequence starts from a string of characters (digits or/and letters) and works as follows – you look at the current symbol and count its frequency. For example, if you look at "22a", you count "two twos" and "one a" so the next sequence element is "221a", and then you repeat this process. You can specify the starting set how many numbers you need and which sequence element to start with. Mathabulous!

Look-and-say number generator examples
Click to use

Generate 8 Look-and-say Numbers

This example calculates eight look-and-say numbers starting from the first element.

1
11
21
1211
111221
312211
13112221
1113213211

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Calculate Five Look-and-say Numbers

This example generates 5 look-and-say numbers starting from the 10th element.

13211311123113112211
11131221133112132113212221
3113112221232112111312211312113211
1321132132111213122112311311222113111221131221
11131221131211131231121113112221121321132132211331222113112211

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Change Sequence Numbers Separator

This example generates 5 look-and-say numbers and changes separator between numbers.

1 | 11 | 21 | 1211 | 111221

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Start the Sequence From a Letter

This example starts the look-and-say sequence from a single character "d". In all the following sequence elements, numbers that describe the sequence frequency always appear before the letter "d". The letter itself always remains on the right side. If you think for a little bit, you'll realize that in any sequence the last element will always remain on the right side and never change.

d; 1d; 111d; 311d; 13211d; 111312211d; 31131122211d; 1321132132211d

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Parentheses in Look-and-say Sequence

In this example, the sequence is formed from two round brackets. In this case, the numbers appear only in front of the opening bracket, and inside the bracket pair. Surprisingly, these numbers are the same! This sequence works for any pair of different characters.

()
1(1)
111(111)
311(311)
13211(13211)
111312211(111312211)

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Growth in Look-and-say Sequence

This example demonstrates that any look-and-say sequence increases over time (except for the degenerate case: 22, 22, 22, ...). In this example the starting alphabet consists of eleven ones. Although a couple of first members decrease in length, the sequence increases with time and grows in length.

11111111111
111
31
1311
111321
31131211
132113111221
1113122113312211

**Required options**

Initial sequence alphabet.

Start generating sequence from
this sequence position.

How many elements to generate?

Separate sequence members
with this symbol.
(Line break "\n" by default.)

Pro tips
Master online math tools

You can pass options to this tool using their codes as query arguments and it will automatically compute output. To get the code of an option, just hover over its icon. Here's how to type it in your browser's address bar. Click to try!

https://onlinemathtools.com/generate-look-and-say-sequence?&first-element=1&count=8&separator=%5Cn&alphabet=1

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