Binary Tree Properties 

Some important properties of a binary tree are as follows:

1. The minimum number of nodes in a binary tree of height H is H+1. 

For example:

To construct a binary tree of height 4 we will need 5 nodes.

       2. The maximum number of nodes is 2^H+1-1. 

For example, the maximum number of nodes in a binary tree of height 3

= 23+1 – 1

= 16 – 1

= 15 nodes

       3. The total number of leaf nodes is equal to the total number of nodes with 2 children+1. 

For example:

      4. The maximum number of nodes at the level “L” is 2^L. For example, the maximum number of nodes at level-2 in a binary tree= 22= 4.

Reference

Binary Tree Properties