def get_full_binary_tree_nodes(height):
return <NUM_LIT:2> ** (height + <NUM_LIT:1>) - <NUM_LIT:1><EOL>
Calculate the number of internal nodes in a complete binary tree in which each
internal node has exactly two children. A full binary tree is complete if every
leaf in the tree has the same depth. Internal nodes include both leaves and
internal nodes. The root node is also included in this calculation.

Args:
    height: integer, the height of the tree. Height is defined by the number
    of edges from the furthest child to the root. An edge is the line segment
    that runs between and connects nodes.