text: Note: "lc" stands for the leading coefficient, the coefficient of the highest degree of the variable.
  This algorithm computes not only the greatest common divisor (the last non zero ), but also all the subresultant polynomials: The remainder  is the -th subresultant polynomial. If , the -th subresultant polynomial is . All the other subresultant polynomials are zero.
  Sturm sequence with pseudo-remainders
  One may use pseudo-remainders for constructing sequences having the same properties as Sturm sequences. This requires to control the signs of the successive pseudo-remainders, in order to have the same signs as in the Sturm sequence. This may be done by defining a modified pseudo-remainder as follows.
  If  and  and , the modified pseudo-remainder  of the pseudo-division of  by  is
  where  is the absolute value of the leading coefficient of  (the coefficient of ).
  For input polynomials with integer coefficients, this allows retrieval of Sturm sequences consisting of polynomials with integer coefficients. The subresultant pseudo-remainder sequence may be modified similarly, in which case the signs of the remainders coincide with those computed over the rationals.
  Note that the algorithm for computing the subresultant pseudo-remainder sequence given above  will compute wrong subresultant polynomials if one uses  instead of .