In an arithmetic sequence the value of the rth term can be calculated through the equation,
Ar = A1 + (r - 1)(d)
where Ar is the rth term, A1 is the first term, r is the number of terms, and d is the common difference.
Substituting the values,
Ar = 34 + (200 - 1)(15) = 3019
Thus, the 15th term of the arithmetic sequence described above is 3019.