$ \begin{tikzpicture}[baseline] \node at (0,.7) (S) [circle,draw] {$S$}; \filldraw (S.180) circle (.5mm); \node at (0,-.7) (S') [circle,draw] {$S$}; \filldraw (S'.180) circle (.5mm); \draw (S.45) -- +(45:4mm); \draw (S.90) node [above] {$\ldots$}; \draw (S.135) -- +(135:4mm); \draw (S'.225) -- +(-135:4mm); \draw (S'.270) node [below] {$\ldots$}; \draw (S'.-45) -- +(-45:4mm); \end{tikzpicture} =\qi{n+1} \cdot \begin{tikzpicture}[baseline] \node (0,0) (JW) [rectangle,draw] {$\quad \JW{k} \quad§·$}; \draw (JW.180); \draw (JW.35) -- +(90:11mm); \draw (JW.90) node [above] {$\cdots$}; \draw (JW.145) -- +(90:11mm); \draw (JW.-35) -- +(-90:11mm); \draw (JW.-90) node [below] {$\cdots$}; \draw (JW.-145) -- +(-90:11mm); \end{tikzpicture} $