Which of the following represents the number of labeled binary trees with ‘n’ node, which have same preorder ?

Question

1. 
2. 
3. 
4. Can not find out

Comments

3. Catalan number?

Answer 1

C option...

Comments

Thank for ans

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catelian no is only for unlabelled tree and in case of labelled tree, the total no of tree is given by: 

plzz clarify me if m wrong