For example, I know that c = A(2,2:2:end); sets c equal to columns {2,4,6,8,10} of row 2 of A
and that c=A(2,2) sets c equal to the number that is in row 2 column 2 of A.
If you only are required to return the nth number I don't see why you'd bother to store them all in an array; you only need the previous two to generate the next one. You should be able to do this with a small set of scalar variables and a loop.
For example, I know that c = A(2,2:2:end); sets c equal to columns {2,4,6,8,10} of row 2 of A
and that c=A(2,2) sets c equal to the number that is in row 2 column 2 of A.
So you're familar with END. Are you aware that f(end) is the last element of vector f?