Let \(A = \left\{ 1,a_{1},a_{2},\ldots,a_{18},77 \right\}\) be a set of integers with \(1 < a_{1} < a_{2} < \ldots < a_{18} < 77\). Let the set \(+ A = \{ x + y\) : \(x,y \in A\}\) contain exactly 39 elements. Then, the value of \(a_{1} + a_{2} + \ldots + a_{18}\) is equal to