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possibleDenominators -- Possible denominators of deformations.

Synopsis

Description

Computes a list L of possible denominators of Laurent monomials representing FirstOrderDeformations of I. The list L is stratified into lists with ascending degree of the denominators. Each denominator is represented as a list of variables.

If the second argument v is given, one obtains only denominators contained (as a list) in v.

i1 : R=QQ[x_0..x_4];
 
i2 : I=ideal(x_0*x_1,x_1*x_2,x_2*x_3,x_3*x_4,x_4*x_0);

o2 : Ideal of R
 
i3 : possibleDenominators(I)

o3 = {{{x }, {x }, {x }, {x }, {x }}, {{x , x }, {x , x }, {x , x }, {x ,
         0     1     2     3     4       0   1     1   2     2   3     0 
     ------------------------------------------------------------------------
     x }, {x , x }}}
      4     3   4

o3 : List
 
i4 : possibleDenominators(I,{x_0,x_1,x_2});

See also

Ways to use possibleDenominators :

For the programmer

The object possibleDenominators is a method function.