  The classical Fourier transform is, in essence, a way to take data and
extract components (in the form of complex exponentials) which are invariant
under cyclic shifts. We consider a case in which the components must instead be
invariant under automorphisms of a binary tree. We present a technique by which
a slightly relaxed form of the generalized Fourier transform in this case can
eventually be computed using only simple tools from linear algebra, which has
possible advantages in computational efficiency.
