\begin{circus}
  \circchannel a \\
  \circprocess P \circdef \circbegin \\
      \circspot (a \then \Skip) \lpar | \lchanset a \rchanset | \rpar ((a \then \Skip) \interleave (((a \then \Skip) \interleave (a \then \Skip)) \lpar | \lchanset a \rchanset | \rpar ((a \then \Skip) \interleave (a \then \Skip))))
  \circend \\
  \end{circus}