Transitive closure relation.

Hi,

The question is as follows:

The transitive closure of a relation R on S x S is another relation on S x S called Tr(R) such that iif there exists a sequence such that for each .

a) What is the transitive closure of the successor relation? (Defined previously on N x N as: ).

b) What is the transitive closure of the > relation?

The book introduced this concept right in this exercise question without showing any examples. I'm a bit stuck as to how I might interpret this somewhat complex definition [of a transitive closure] and derive the solution.