Answer is:

**1**

1 1

2 1

1 2 1 1

1 1 1 2 2 1

3 1 2 2 1 1

1 3 1 1 2 2 2 1

Logic is:

Just started with 1 in first line and printed **successive repeating counts of each no. and the no** in the successive lines.

First line ---> **1**

Second line ---> No. of ones is 1. --> **one 1 --> 1 1**

Third line ---> No. of ones is 2. --> **two 1 --> 2 1**

Fourth line---> No. of twos is 1 and no. of ones is 1 --> **one 2 one 1 --> 1 2 1 1**

Fifth line---> No. of ones is 1 and no. of twos is 1 and no. of ones is 2 -->** one 1 one 2 two 1 --> 1 1 1 2 2 1**

Similarly for fifth and sixth line:

No. of ones is 3 and no. of twos is 2 no. of ones is 1 --> **three 1 two 2 one 1 --> 3 1 2 2 1 1**

No. of threes is 1 and no. of ones is 1 and no. of twos is 2 and no. of ones is 2 --> **one 3 one 1 two 2 two 1 --> 1 3 1 1 2 2 2 1**