Function monomial_orbits 

pub fn monomial_orbits(
    num_vars: usize,
    degree: usize,
    generators: &[Perm],
) -> Vec<Vec<Mono>>

Symmetry-break Polynomial Calculus at the basis. Partition the degree-≤degree monomials into orbits under the formula’s automorphisms. The orbit count is the width of the symmetry-reduced Nullstellensatz system — a symmetric certificate is constant on each orbit, so the Gaussian runs over the quotient instead of all C(n,d) monomials. The same collapse that made the field cuts O(1), inherited by the algebraic engine. (Bounded to num_vars ≤ 20.)