_{1}, d

_{2}, d

_{3}, ...d

_{n-1}, d

_{n}... represent the sequence of consecutive differences of another sequence T: t

_{1}, t

_{2}, t

_{3}, ...t

_{n-1}, t

_{n}.

Given t_{1}=0 , and t_{k}-t_{k-1}=d_{k-1}=k, provide definition and formula for the sequence T.