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ArrExponents    --    exponents of a free arrangement of hyperplanes


Syntax 
ArrExponents(Q: RINGELEM): LIST

Description
This function returns the list of exponents of a free arrangement of hyperplanes from its defining equation Q.

Example 
/**/ use QQ[x,y];	
/**/ A := [x, x-y, y]; -- free
/**/ Q_A := product(A);	
/**/ ArrExponents(Q_A);
[1,  2]
	
/**/ use QQ[x,y,z];
/**/ A := [x, x+z, y, 2*y-3*z]; -- not free
/**/ IsArrFree(product(A)); --> false
-- /**/ ArrExponents(product(A));  --> !!! ERROR !!! as expected, not free

See Also