Sequencing

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  Q. Next number in the sequence: 2, 12, 1112, 3112, 132112, 1113122112, ?

Solution:

This is a look-and-say sequence.

for example (2)- there is one number of digit two so-> 12

now for (12)- there is one number of digit 1 and one number of digit 2->1112

Each term describes the previous term's digits.

After 1113122112 → next is 311311222112

In words: there are three 1 and one 3, one 1 and two 2, two 1 and one 2.