<<< native [ EArray [ AlignCenter ] [ [ [ EIdentifier "H" ] ] , [ [ EIdentifier "T" ] ] , [ [ EIdentifier "U" ] ] ] , ESymbol Rel "=" , EArray [ AlignCenter ] [ [ [ EIdentifier "H" ] ] , [ [ EIdentifier "T" ] ] , [ [ EIdentifier "U" ] ] ] ] >>> tex \begin{matrix} H \\ T \\ U \end{matrix} = \begin{matrix} H \\ T \\ U \end{matrix}