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DenSigma

den of ideal, wrt to ordering sigma

Syntax
DenSigma(I: IDEAL): RINGELEM

Description
This function returns the sigma-denominator of the ideal I , that is the common denominator of all polynomials in the sigma-reduced GBasis.

See article Abbott, Bigatti, Robbiano "Ideals modulo p" ( https://arxiv.org/abs/1801.06112 )

Example
/**/ use QQ[x,y,z];
/**/ I := ideal(2*x*y^2 -1, 3*x^3*y -1);
/**/ ReducedGBasis(I);
[x*y^2 -1/2,  x^2 +(-2/3)*y,  y^3 +(-3/4)*x]
/**/ DenSigma(I);
12

See Also