n-th term in series 2, 12, 36, 80, 150....

Given a series 2, 12, 36, 80, 150.. Find the n-th term of the series.
Examples : 
 

Input : 2
Output : 12

Input : 4
Output : 80 

If we take a closer look, we can notice that series is sum of squares and cubes of natural numbers (1, 4, 9, 16, 25, .....) + (1, 8, 27, 64, 125, ....).
Therefore n-th number of the series is n^2 + n^3 
 

Output : 
 

80

Time complexity: O(1) as only single step is required to calculate nth term from given formula

Auxiliary Space: O(1)