<Section> <Heading>Gaps</Heading> A <E>gap</E> of a numerical semigroup <M>S</M> is a nonnegative integer not belonging to <M>S</M>. The <E>fundamental gaps</E> of <M>S</M> are those gaps that are maximal with respect to the partial order induced by division in <M>{\mathbb N}</M>. The <E>special gaps</E> of a numerical semigroup <M>S</M>, are those fundamental gaps such that if they are added to the given numerical semigroup, then the resulting set is again a numerical semigroup. <ManSection> <Attr Name="GapsOfNumericalSemigroup" Arg="NS"/> <Description> <C>NS</C> is a numerical semigroup. It returns the set of gaps of <C>NS</C>. <Example><![CDATA[ gap> GapsOfNumericalSemigroup(NumericalSemigroup(3,5,7)); [ 1, 2, 4 ] ]]></Example> </Description> </ManSection> <ManSection> <Attr Name="FundamentalGapsOfNumericalSemigroup" Arg="S"/> <Description> <C>S</C> is a numerical semigroup. It returns the set of fundamental gaps of <A>S</A>. <Example><![CDATA[ gap> S := NumericalSemigroup("modular", 5,53); <Modular numerical semigroup satisfying 5x mod 53 <= x > gap> FundamentalGapsOfNumericalSemigroup(S); [ 16, 17, 18, 19, 27, 28, 29, 30, 31, 40, 41, 42 ] gap> GapsOfNumericalSemigroup(S); [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 14, 15, 16, 17, 18, 19, 20, 21, 27, 28, 29, 30, 31, 40, 41, 42 ] ]]></Example> </Description> </ManSection> <ManSection> <Attr Name="SpecialGapsOfNumericalSemigroup" Arg="S"/> <Description> <C>S</C> is a numerical semigroup. It returns the special gaps of <A>S</A>. <Example><![CDATA[ gap> S := NumericalSemigroup("modular", 5,53); <Modular numerical semigroup satisfying 5x mod 53 <= x > gap> SpecialGapsOfNumericalSemigroup(S); [ 40, 41, 42 ] ]]></Example> </Description> </ManSection> </Section>