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ArrPoincarePoly

Poincare polynomial of an arrangement of hyperplanes

Syntax
ArrPoincarePoly(A: LIST): RINGELEM

Description
This function returns the Poincare polynomial from the list A of hyperplanes in the arrangement in the variable t.

Example
/**/ use QQ[x,y];	
/**/ A := [x, x-y, y];
/**/ ArrPoincarePoly(A);
2*t^2 +3*t +1

See Also