Let \( a_{n} \) be the \( n \)th term of the series \( 5+8+14+23+35+50+\ldots \) and \( s_{n}=\displaystyle\sum_{k=1}^{n}a_{k} \). Then \( S_{30}-a_{40} \) is equal to:
\( 11290 \)
\( 11260 \)
\( 11280 \)
\( 11310 \)