Difficulty: Easy  Medium
Pre requisites: Basic mathematics
Problem link:
Problem:
To find the nth number in the series:
1 2 7 20 61…
Explanation:
The problem requires you to identify the pattern of growth of the sequence mentioned in the problem.

It is a series where the number at nth position is
T(n)=2*T(n1)+3*T(n2)
Problem setter’s solution: SOLUTION