By 
Alex Gendler
 | 
TED-Ed Original

Can you find the next number in this sequence?

1 11 21 1211 111221. These are the first five elements of a number sequence. Can you figure out what comes next? Alex Gendler reveals the answer and explains how beyond just being a neat puzzle this type of sequence has practical applications as well.

Related tags:

TED is supported by ads and partners

Watch next