Sequences And Series

Let \(\mathrm{a}_{\mathrm{n}}\) be the \(\mathrm{n}^{\text {th }}\) term of the series \(5+8+14+23+35+50+\ldots\) and \(\mathrm{S}_{\mathrm{n}}=\sum_\limits{k=1}^{n} a_{k}\). Then \(\mathrm{S}_{30}-a_{40}\) is equal to :