lol.
z
1z
111z
311z
13211z
?
each line describes the previous line. there's one alphabet z in each line, so its 1z. thats the second line. the third line describes the second line. theres one of the number 1 there, so its 11, and one of the alphabet z, so its 1z. then the fourth line describes the third line. there are 3 of the number 1 in the third line, so its 31, and then one of the alphabet z, so its 1z. then the fifth line describes the fourth line. there's 1 of the number 3, 2 of the number 1, and 1 of the alphabet z. so well, thats it lol.. look at each number/letter in order, and if there's a few of the same one group them together