Theorem 4.7
Let
be a cubic form. This algorithm
outputs true or false according to whether F corresponds to
the image of a cubic field by the Davenport-Heilbronn map.
- If F is not irreducible, return false.
- If F is not primitive, return false.
- Compute the Hessian
by the formulas given. Set
,
(so
). Using Proposition 3.3, check
that
and
, otherwise return false.
- If
for some p>3, return false.
- Set
. Remove all powers of 2 and 3 from t (in fact at most
and
), and let again t be the result. If
return false.
- If t is squarefree return true, otherwise return false.
Annotation Form Interface