secMilnorNumbers f
Let origin be an isolated singular point of a complex analytic hypersurface $H = V(f).$ The $\mathbb{C}$-vector space dimension of $\mathbb{C}\{x_0,\ldots,x_n\}/(f_{x_0},\ldots,f_{x_n})$ is called the Milnor number of the hypersurface $H$ at the origin. Let $(X, 0)$ be a germ of a hypersurface in $\mathbb{C}^{n+1}$ with an isolated singularity at the origin. The Milnor number of $X \cap E$, where $E$ is a general linear subspace of dimension $i$ passing through the origin, is called the $i$-th sectional Milnor number of $X$. B. Teissier identified the $i$-th sectional Milnor number with the $i$-th mixed multiplicity of the maximal homogeneous ideal of the polynomial ring and the Jacobian ideal of $f.$
Let $f$ be an element of a polynomial ring $R$ with characteristic zero, and let $d$ be the dimension of $R$. The function computes the sectional Milnor numbers by computing the mixed multiplicities $e_0(m|J(f)),\ldots,e_{d}(m|J(f))$, where $m$ is the maximal homogeneous ideal of $R$ and $J(f)$ is the Jacobian ideal of $f$ of height $d$. Note that in this case, the last sectional Milnor number $e_d(m|J(f))$ is the Milnor number of $f.$
In this example, the 2-sectional Milnor number, which is the Milnor number of a general hypersurface section, is 28. The Milnor number, which is the last sectional Milnor number, is 364.
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The user is supposed to check that the given polynomial defines an isolated singularity at the homogeneous maximal ideal.
The object secMilnorNumbers is a method function.