1, 11, 31, 4113, 612314, ? , ?

(Explain how you arrived at your result).

I believe each is created using the amount of a certain number using all the previous numbers.

81 12 33 24 16

eight 1's, one 2, three 3's etc.. 

heh its also kinda funny b/c i was creating a desktop background based on a similar sequence

1 11 21 1211 3112 etc..