DefectApproximation( L )
computes a multiple of the defect of the basis of L, given by the
powers of the primitive element. The defect indicates, which
denominator is necessary in the coefficients, to express algebraic
integers in L as a linear combination of the base of L.
DefectApproximation takes the maximal square in the discriminant as a
first approximation, and then uses Berwicks and Hesses method (see
Bra89) to improve this approximation. The number returned is not
neccessarily the defect, but may be a proper multiple of it.
gap> DefectApproximation(e);
1
GAP 3.4.4