by the sum $$\mathcal {P}=D_{3}+D_{4}+D_{6}+D_{9}+D_{11}+D_{12}-D_{13}+D_{14}+D_{16}+B_{1}+B_{2}+\ldots +B_{n-3}\;.$$ Applying the first Chern class formula [@OS2 Proposition 7.5] we obtain $$\begin{aligned}
\left \langle c_{1}(\mathfrak{s}_{z}(\mathbf{x})),\mathcal {P}\right \rangle & =\chi (\mathcal{P})+2\sum _{x_{i}\in \mathbf{x}}\overline{n}_{x_{i}}(\mathcal{P})=3(1-\frac {6}{4})+(-1)(1-\frac {2}{4})+2\sum _{x_{i}\in \mathbf{x}}\overline{n}_{x_{i}}(\mathcal{P})=\\
&=2\left (\sum _{x_{i}\in \mathbf{x}}\overline{n}_{x_{i}}(\mathcal{P})-1\right )\;,\end{aligned}$$

\[t\] at 365 316 \[b\] at 290 470 \[t\] at 338 606 at 125 400 at 170 450 at 216 440 \[b\] at 283 316 \[b\] at 300 316 \[b\] at 318 316 \[b\] at 333 316 \[b\] at 372 316 \[b\] at 350 316 \[b\] at 395 316 \[b\] at 385 316 \[t\] at 400 314 \[b\] at 312 470 \[b\] at 342 470 \[b\] at 362 470 \[b\] at 375 470 \[b\] at 326 470 \[t\] at 358 468 \[b\] at 340 610 \[b\] at 382 610 \[b\] at 366 610 \[b\] at 402 610 \[b\] at 280 610 \[b\] at 296 610 \[b\] at 320 610 \[b\] at 354 610 at 470 470 at 420 260 at 296 725 at 387 250 at 296 711 at 250 500 at 296 690 at 373 252 at 230 424 at 363 260 at 374 424 at 200 612 at 345 270 at 320 390 at 315 530 at 352 380 at 352 