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EvalHilbertFn

evaluate the Hilbert function

Syntax
EvalHilbertFn(H:TAGGED("$hp.Hilbert"), N: INT): INT

Description
This function evaluates the Hilbert function H at N. If H is the Hilbert function of a quotient R/I, then the value returned is the same as that returned by HilbertFn(R/I, N) but time is saved since the Hilbert function does not need to be recalculated at each call.

Example
/**/  use R ::= QQ[w,x,y,z];
/**/  I := ideal(z^2-x*y, x*z^2+w^3);
/**/  H := HilbertFn(R/I);
/**/  H;
H(0) = 1
H(1) = 4
H(t) = 6t - 3   for t >= 2

/**/  EvalHilbertFn(H,1);
4
/**/  EvalHilbertFn(H,2);
9

See Also