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HVector --
the h-vector of a module or quotient object
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HVector(M: (Poly or Quotient)RING): LIST
HVector(M: MODULE): LIST |
This function returns the h-vector of
M, i.e. the coefficients of the
numerator of the simplified Poincare series for
M.
M can be a
module or a quotient.
The weights of the indeterminates of the polynomial ring of
M must all
be 1, and the coefficient ring must be a field.
If the input is not homogeneous, the Hilbert function of the
corresponding leading term (initial) ideal or module is calculated.
/**/ use R ::= QQ[t,x,y,z];
/**/ HVector(R/ideal(x,y,z)^5);
[1, 3, 6, 10, 15]
/**/ HilbertSeries(R/ideal(x,y,z)^5);
(1 + 3t + 6t^2 + 10t^3 + 15t^4) / (1-t)
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