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RegularityIndex

regularity index of a Hilbert function or series
Syntax

RegularityIndex(R:RING or TAGGED("Quotient")):INT


Description
This function computes the regularity index of a Hilbert function. The input might be expressed as a Hilbert function or as the corresponding Hilbert series (computed with standard weights).

Example
  Use R ::= QQ[x,y,z];
  Quot := R/Ideal(x^3, y^2);
  HilbertFn(Quot);
H(0) = 1
H(1) = 3
H(2) = 5
H(t) = 6   for t >= 3
-------------------------------
  RegularityIndex(Hilbert(Quot));
3
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  RegularityIndex(Poincare(Quot));
3
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See Also