Ramanujan-Diophantus

Number Theory Level 4

$\large 17R + 29D = 1729$

Let $(R_1, D_1), (R_2, D_2) , \ldots , (R_n, D_n)$ be the positive integer pair of roots to the equation above. Find the value of $\displaystyle \sum_{i=1}^n (R_i + D_i)$ .