  We compute numerically the dimensions and OPE coefficients of several
operators in the 3d Ising CFT, and then try to reverse-engineer the solution to
crossing symmetry analytically. Our key tool is a set of new techniques for
computing infinite sums of SL(2,R) conformal blocks. Using these techniques, we
solve the lightcone bootstrap to all orders in an asymptotic expansion in large
spin, and suggest a strategy for going beyond the large spin limit. We carry
out the first steps of this strategy for the 3d Ising CFT, deriving analytic
approximations for the dimensions and OPE coefficients of several infinite
families of operators in terms of the initial data
$\{\Delta_\sigma,\Delta_\epsilon,f_{\sigma\sigma\epsilon},f_{\epsilon\epsilon\epsilon},c_T\}$.
The analytic results agree with numerics to high precision for about 100
low-twist operators (correctly accounting for O(1) mixing effects between
large-spin families). Plugging these results back into the crossing equations,
we obtain approximate analytic constraints on the initial data.
