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	\begin{pgfonlayer}{nodelayer}
		\node [style=white node] (1) at (0, 0) {};
		\node [style=black node] (2) at (-2, 0) {};
		\node [style=black node] (3) at (2, 0) {};
		\node [style=white node] (4) at (1, 2) {};
		\node [style=white node] (5) at (-1, 2) {};
		\node [style=black node] (6) at (0, 4) {};
		\node [style=black node] (7) at (2, 8) {};
		\node [style=white node] (8) at (1, 6) {};
		\node [style=white node] (9) at (3, 10) {};
		\node [style=black node] (10) at (4, 12) {};
		\node [style=white node] (11) at (5, 10) {};
		\node [style=white node] (12) at (7, 6) {};
		\node [style=white node] (13) at (9, 2) {};
		\node [style=black node] (14) at (6, 8) {};
		\node [style=black node] (15) at (8, 4) {};
		\node [style=black node] (16) at (10, 0) {};
		\node [style=black node] (17) at (6, 0) {};
		\node [style=white node] (18) at (8, 0) {};
		\node [style=white node] (19) at (7, 2) {};
	\end{pgfonlayer}
	\begin{pgfonlayer}{edgelayer}
		\draw (1) to (3);
		\draw (2) to (1);
		\draw (2) to (4);
		\draw (2) to (5);
		\draw (5) to (6);
		\draw (6) to (8);
		\draw (8) to (7);
		\draw (7) to (9);
		\draw (9) to (10);
		\draw (10) to (11);
		\draw (11) to (14);
		\draw (12) to (14);
		\draw (15) to (12);
		\draw (15) to (13);
		\draw (16) to (13);
		\draw (16) to (18);
		\draw (18) to (17);
		\draw (16) to (19);
	\end{pgfonlayer}
	\begin{pgfonlayer}{background}
	\fill[cyan,opacity=1] \convexpath{1,3,2}{8pt};
	\fill[cyan,opacity=1] \convexpath{2,4}{8pt};	
	\fill[cyan,opacity=1] \convexpath{2,5,6,7,8,9}{8pt};		

	\fill[cyan,opacity=1] \convexpath{11,12,13,14,15,16}{8pt};
	\fill[cyan,opacity=1] \convexpath{16,17}{8pt};	
	\fill[cyan,opacity=1] \convexpath{16,19}{8pt};		
	\end{pgfonlayer}
\end{tikzpicture}
