Evil & Odious

A non-negative integer is called evil if it has an even number of ones in its binary representation. Similarly, a non-negative integer is called odious if it has an odd number of ones in its binary representation. Let us write down evil and odious numbers in ascending order.

Let $E(n)$ be the $n$-th evil number in this list. Similarly, let $O(n)$ be the $n$-th odious number.

Write a program to calculate the sum of $n$-th evil and odious numbers E(n) + O(n) given their index $n$.