[\begin{align} p _{n+1} &= p _n+K\sin(x_n) \mod 2\pi\newline x _{n+1} &= x _n +p _{n+1} \mod 2\pi \end{align}]
based on Complexity Explorable:
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Kick it like Chirikov
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Explore the chaotic sea of a famous two-dimensional map
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