\begin{tikzpicture}[baseline]
    \clip (-.8,-1.3) rectangle (1,1.3);

    \node at (0,.7) (top) [rectangle,draw] {$  \JW{2n-2} $};
    \node at (0,-.7) (bottom) [ellipse,draw]{$ \hspace{.15 cm} S \hspace{.15cm} $};
    \filldraw (bottom.180) circle (.5mm);    

    \draw (top.-60)--(bottom.60);
    \draw (top.-145)--(bottom.145);
    \node at (-.1,0) {...};
    \draw (top.-35) -- (bottom.35);

    \draw (top.35) -- ++(90:1cm);
    \draw (top.60) -- ++(90:1cm);
    \node at (-.1,1.2) {...};
    \draw (top.145) -- ++(90:1cm);

    \draw (bottom.-35) -- ++(-90:1cm);
    \draw (bottom.-60) -- ++(-90:1cm);
    \node at (-.1,-1.2) {...};
    \draw (bottom.-145) -- ++(-90:1cm);
\end{tikzpicture}
+
\begin{tikzpicture}[baseline]
    \clip (-.8,-1.3) rectangle (1,1.3);

    \node at (0,.7) (top) [ellipse,draw] {$ \hspace{.15 cm} S \hspace{.15cm} $};
    \node at (0,-.7) (bottom) [rectangle,draw] {$  \JW{2n-2} $};
    \filldraw (top.180) circle (.5mm);

    \draw (top.-60)--(bottom.60);
    \draw (top.-145)--(bottom.145);
    \node at (-.1,0) {...};
    \draw (top.-35) -- (bottom.35);

    \draw (top.35) -- ++(90:1cm);
    \draw (top.60) -- ++(90:1cm);
    \node at (-.1,1.2) {...};
    \draw (top.145) -- ++(90:1cm);

    \draw (bottom.-35) -- ++(-90:1cm);
    \draw (bottom.-60) -- ++(-90:1cm);
    \node at (-.1,-1.2) {...};
    \draw (bottom.-145) -- ++(-90:1cm);
\end{tikzpicture}
& = \frac{2}{\qi{2}}
\begin{tikzpicture}[baseline]
    \clip (-.7,-1.3) rectangle (1.5,1.3);
    \node at (0,0) (box) [ellipse,draw] {$ \hspace{.15 cm} S \hspace{.15cm} $};
    \filldraw (box.180) circle (.5mm);

    \draw (box.-145)--++(-90:1cm);
    \node at (box.-90) [below] {...};
    \draw (box.-35) -- ++(-90:1cm);

    \draw (box.35) -- ++(90:1cm);
    \node at (box.90) [above] {...};
    \draw (box.145) -- ++(90:1cm);

    \draw (.9,.5)--(.9,-.5) arc (-180:0:.2cm) -- ++(90:1cm) arc (0:180:.2cm);
\end{tikzpicture}
=
2
\begin{tikzpicture}[baseline]
    \clip (-.7,-1.3) rectangle (.7,1.3);
    \node at (0,0) (box) [ellipse,draw] {$ \hspace{.15 cm} S \hspace{.15cm} $};
    \filldraw (box.180) circle (.5mm);

    \draw (box.-145)--++(-90:1cm);
    \node at (box.-90) [below] {...};
    \draw (box.-35) -- ++(-90:1cm);

    \draw (box.35) -- ++(90:1cm);
    \node at (box.90) [above] {...};
    \draw (box.145) -- ++(90:1cm);
\end{tikzpicture}
