  We prove three supercongruences for sums of Almkvist-Zudilin numbers, which
confirm some conjectures of Zudilin and Z.-H. Sun. A typical example is the
Ramanujan-type supercongruence: \begin{align*} \sum_{k=0}^{p-1}
\frac{4k+1}{81^k}\gamma_k \equiv \left(\frac{-3}{p}\right) p\pmod{p^3},
\end{align*} which is corresponding to Chan and Verrill's formula for $1/\pi$:
\begin{align*} \sum_{k=0}^\infty \frac{4k+1}{81^k}\gamma_k =
\frac{3\sqrt{3}}{2\pi}. \end{align*} Here $\gamma_n$ are the Almkvist-Zudilin
numbers.
