Problem 888. Create a vector whose elements depend on the previous element

The idea is to create a vector A whose elements depend on the previous element : A(i+1) = 2*A(i)+1

2 Inputs:

- A : The first value of the vector

- iterations : The number of iterations

1 Output:

- A a vector with iterations+1 elements such as the i+1 element depend on the previous element as follows :

A(i+1) = 2*A(i)+1

Example :

A = 1;
iterations = 4;

The expected output vector has 5 elements :

A = [1     3     7    15    31]

A(2) =3 because A(2) =2*A(1)+1 = 2*1+1 = 3

A(3) = 7 because A(3) =2*A(2)+1 ...