This sequent is provable. \begin{logicproof}{1} (p \land q) \lor (p \land r) & \prem \\ \begin{subproof} p \land q & \assum \\ p & $\ande{1} 2$ \end{subproof} \begin{subproof} p \land r & \assum \\ p & $\ande{1} 4$ \end{subproof} p & $\ore 1, 2-3, 4-5$ \\ \begin{subproof} p \land q & \assum \\ q & $\ande{2} 7$ \\ q \lor r & $\ori 8$ \end{subproof} \begin{subproof} p \land r & \assum \\ r & $\ande{2} 10$ \\ q \lor r & $\ori 11$ \end{subproof} q \lor r & $\ore 1, 7-9, 10-12$ \\ p \land (q \lor r) & $\andi 6, 13$ \end{logicproof}