The first questions (1 through 4) in this section contain the initial entries in a few sequences of numbers.  For each of these problems, your answer should specify the following three things:
What are the next three elements of the sequence?
If one element in the sequence has value x, what is the value of the next element in the sequence?
What is element i in the sequence (as a function of i)?  Note that I'm assuming that the first element in the sequence is element 0.
For example, if the given sequence was 1, 3, 5, 7, 9, 11,... then your answers should be:

13, 15, 17 (since these are clearly just listing odd numbers)
x + 2 (since each odd number is two larger than the previous odd number)
2i + 1 (since odd number i is twice i plus 1)