\begin{center}
\footnotesize
\setlength{\mylength}{\baselineskip}
\begin{longtable}{rp{0ex}p{9cm}p{0ex}RL}
\caption{Laurent polynomials and selected mutations for bucket 21.}\\

\toprule \multicolumn{1}{c}{{Node}}&& \multicolumn{1}{c}{{Laurent polynomial}} && \multicolumn{2}{c}{{Mutations from Figure~\ref{fig:21a}}} \\ \midrule \endfirsthead

\multicolumn{6}{c}{{\tablename\ \thetable{} -- continued from previous page}} \\ \addlinespace[1.7ex] \midrule \multicolumn{1}{c}{{Node}}&& \multicolumn{1}{c}{{Laurent polynomial}} && \multicolumn{2}{c}{{Mutations from Figure~\ref{fig:21a}}} \\ \midrule \endhead

\midrule \multicolumn{6}{c}{{Continued on next page}} \endfoot

\bottomrule \endlastfoot

143 && $\frac{x^2}{yz}+x+\frac{3x}{yz}+y+z+\frac{3}{yz}+\frac{1}{x}+\frac{1}{xyz}$ && $186 \colon {}$ & $\left(x,y,\frac{(x+1)^2}{yz}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \rowcolor[gray]{0.95}
186 && $\frac{x^2}{yz}+x+\frac{2x}{yz}+y+z+\frac{1}{yz}+\frac{z}{x}+\frac{1}{x}$ && $143 \colon {}$ & $\left(x,y,\frac{(x+1)^2}{yz}\right)$ \spacer \\* \rowcolor[gray]{0.95}
 &&  && $308 \colon {}$ & $\left(\frac{yz}{x(yz^2+yz+1)},y,\frac{yz^2}{x(yz^2+yz+1)}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 203 && $\frac{x^2}{yz}+x+\frac{x}{yz}+y+z+\frac{y}{x}+\frac{z}{x}+\frac{1}{x}$ && $686 \colon {}$ & $\left(\frac{xyz}{yz^2+yz+1},\frac{x}{yz^2+yz+1},y\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \rowcolor[gray]{0.95}
308 && $xz+x+\frac{x}{y}+\frac{2x}{yz}+\frac{x}{y^2z^2}+y+z+\frac{2}{yz}+\frac{1}{x}$ && $186 \colon {}$ & $\left(\frac{yz}{x^2+xyz+yz^2},y,\frac{z}{x}\right)$ \spacer \\* \rowcolor[gray]{0.95}
 &&  && $1013 \colon {}$ & $\left(\frac{xyz+1}{x^2yz},\frac{xyz+1}{xy},y\right)$ \spacer \\* \rowcolor[gray]{0.95}
 &&  && $1340 \colon {}$ & $\left(\frac{x^3y^2z}{x^2y^2+z(xy+1)^2},\frac{x^3y^2}{x^2y^2+z(xy+1)^2},\frac{x^2y^2+z(xy+1)^2}{x^2y}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 686 && $x+y+z+\frac{1}{yz}+\frac{yz}{x}+\frac{y}{x}+\frac{z}{x}+\frac{1}{x}+\frac{1}{xz}+\frac{1}{xyz}$ && $203 \colon {}$ & $\left(\frac{x^2+xyz+y^2z}{yz},z,\frac{x}{yz}\right)$ \spacer \\* 
 &&  && $1013 \colon {}$ & $\left(x,\frac{xz}{x+y+1},\frac{x+y+1}{xyz}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \rowcolor[gray]{0.95}
949 && $x+y+z+\frac{z}{y}+\frac{y}{x}+\frac{1}{x}+\frac{2}{xz}+\frac{1}{xy}+\frac{y}{x^2z}+\frac{2}{x^2z}+\frac{1}{x^3z^2}$ && $1340 \colon {}$ & $\left(x,\frac{xy}{z(x^2y+xy+1)},y\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 1013 && $x+y+z+\frac{1}{yz}+\frac{y}{x}+\frac{1}{x}+\frac{1}{xz}+\frac{1}{xy}+\frac{2}{xyz}+\frac{1}{x^2z}+\frac{1}{x^2yz}$ && $308 \colon {}$ & $\left(\frac{x+yz}{xyz},z,\frac{y^2z}{x+yz}\right)$ \spacer \\* 
 &&  && $686 \colon {}$ & $\left(x,\frac{1}{yz},\frac{xyz+yz+1}{xz}\right)$ \spacer \\* 
 &&  && $1390 \colon {}$ & $\left(x,\frac{xz}{x+1},\frac{1}{yz}\right)$ \spacer \\* 
 &&  && $1719 \colon {}$ & $\left(\frac{(y+z)(yz+z+1)}{xyz},y,\frac{xy}{(y+z)(yz+z+1)}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \rowcolor[gray]{0.95}
1340 && $xyz+x+yz+y+z+\frac{2z}{x}+\frac{1}{x}+\frac{1}{xz}+\frac{2}{xy}+\frac{z}{x^2y}+\frac{2}{x^2y}+\frac{1}{x^3y^2}$ && $308 \colon {}$ & $\left(\frac{y^3z^2+x(yz+1)^2}{y^2z^2},\frac{y^3z^3}{y^3z^2+x(yz+1)^2},\frac{x}{y}\right)$ \spacer \\* \rowcolor[gray]{0.95}
 &&  && $949 \colon {}$ & $\left(x,z,\frac{xz}{y(x^2z+xz+1)}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 1390 && $x+y+z+\frac{1}{yz}+\frac{yz}{x}+\frac{3y}{x}+\frac{1}{x}+\frac{1}{xz}+\frac{yz}{x^2}+\frac{3y}{x^2}+\frac{1}{x^2z}+\frac{y}{x^3}$ && $1013 \colon {}$ & $\left(x,\frac{x}{yz(x+1)},\frac{y(x+1)}{x}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \rowcolor[gray]{0.95}
1719 && $x+y+z+\frac{2z}{y}+\frac{y}{x}+\frac{2z}{x}+\frac{1}{x}+\frac{1}{xz}+\frac{z^2}{xy}+\frac{2z}{xy}+\frac{2}{xy}+\frac{z^2}{xy^2}+\frac{z}{xy^2}$ && $1013 \colon {}$ & $\left(\frac{(xz+y+1)(xyz+1)}{x^2yz},y,\frac{1}{xz}\right)$ \bottomspacer \\ \addlinespace[1.1ex]
 \end{longtable}
\end{center}
