Baldwin enumeration: |favored|=20, |disfavored|=10, total=30 = 5·2·3

Sympy-exact witness of the Baldwin-rules enumeration. Setup: build the full Cartesian product {3,4,5,6,7} × {exo, endo} × {tet, trig, dig} — 30 triples. Favored set F (20 triples): exo-tet all 5, exo-trig all 5, exo-dig {5,6,7} 3,…