Puzzle #2: 1 11 21 ?

Yeah, you read it right... the puzzle starts like this: 1 11 21 ? 

So what is the next number?

Ok, to give you one more clue: 1 11 21 1211 ?

Still not getting it? How about: 1 11 21 1211 111221 ?

Hecks, I can go on and on...but based on my experience, most people cannot figure out the pattern of the numbers, thus could not get the answer...

I first encountered this puzzle when I was in Form 6...when I knew the answer, I realized it was nothing complex about this sequence of integers...in fact, it was VERY, VERY EASY, lol... it reminds me of the astronaut pen story and the soap box story, haha...

So it goes like this:

1 is read as "one 1", hence 11.
11 is read as "two 1s", hence 21.
21 is read as "one 2, then one 1", hence 1211.
1211 is read as "one 1, then one 2, then two 1s", hence 111221.
111221 is read as "three 1s, then two 2s, then one 1", hence 312211
and it goes on and on....

Ok, take this...so what is the next integer?

See also all-time top post: Matchstick Puzzle