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{ s t } → { z h d h } / D h {\displaystyle {\begin{Bmatrix}s\\t\end{Bmatrix}}\to {\begin{Bmatrix}z^{h}\\d^{h}\end{Bmatrix}}\ /{\text{D}}^{\text{h}}}
{st} → {zʰdʰ} /Dʰ
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