Reconstructing inflation in scalar-torsion $f(T,\phi)$ gravity
  It is investigated the reconstruction during the slow-roll inflation in the
most general class of scalar-torsion theories whose Lagrangian density is an
arbitrary function $f(T,\phi)$ of the torsion scalar $T$ of teleparallel
gravity and the inflaton $\phi$. For the class of theories with Lagrangian
density $f(T,\phi)=-M_{pl}^{2} T/2 - G(T) F(\phi) - V(\phi)$, with $G(T)\sim
T^{s+1}$ and the power $s$ as constant, we consider a reconstruction scheme for
determining both the non-minimal coupling function $F(\phi)$ and the scalar
potential $V(\phi)$ through the parametrization (or attractor) of the scalar
spectral index $n_{s}(N)$ and the tensor-to-scalar ratio $r(N)$ as functions of
the number of $e-$folds $N$. As specific examples, we analyze the attractors
$n_{s}-1 \propto 1/N$ and $r\propto 1/N$, as well as the case $r\propto 1/N
(N+\gamma)$ with $\gamma$ a dimensionless constant. In this sense and depending
on the attractors considered, we obtain different expressions for the function
$F(\phi)$ and the potential $V(\phi)$, as also the constraints on the
parameters present in our model and its reconstruction.
