  P. Alonso-Ruiz, U. Freiberg and J. Kigami have defined a large family of
resistance forms on the Stretched Sierpinski Gasket $G$. In the present paper
we introduce a system of coordinates on $G$ (technically, an embedding of $G$
into $\R^2$) such that
  \noindent$\bullet$) these forms are defined on $C^1(\R^2,\R)$ and
  \noindent$\bullet$) all affine functions are harmonic for them.
  We do this adapting a standard method from the Harmonic Sierpinski Gasket: we
start finding a sequence $G_l$ of pre-fractals such that all affine functions
are harmonic on $G_l$. After showing that this property is inherited by the
stretched harmonic gasket $G$, we use the formula for the Laplacian of a
composition to prove that, for a natural measure $\mu$ on $G$,
$C^2(\R^2,\R)\subset\dc(\Delta)$ and Teplyaev's formula for the Laplacian of
$C^2$ functions holds. Lastly, we use the expression for $\Delta u$ to show
that the form we have found is closable in $L^2(G,\mu)$.
