Function eval_eq_uni 

pub fn eval_eq_uni<F: Field>(l_skip: usize, x: F, y: F) -> F

Let D be the univariate skip domain, the subgroup of F^* of order 2^l_skip.

Computes the polynomial text eq_D(X, Y) = \sum_{z_1 \in D} \prod_{z_2 \in D, z_2 != z_1} (X - z_1)(Y - z_2) / (z_1 - z_2)^2