Here is a sequence of numbers:

1 11 21 1211 111221

It seems to be a strange sequence, but there is a system behind it...

The question: What is the next term in this sequence?

The answer: Click here!

Another question: Here is another sequence of numbers:

1 11 21 1211 1231 131221

What is the next term in this sequence?

Another answer: Click here!