4 problems

Orlik–Randell's conjecture. The basis constructed by Orlik and Randell is distinguished, and its Seifert matrix is

Let $\widetilde f$ be the Berglund--Hübsch transpose of the chain-type invertible polynomial, and let $\chi_n$ denote the matrix appearing in the Orlik--Randell description of the…

Let $S$ be a matrix in a Seifert form stratum of $T(n,\mathbb R)$ that is not met by $\bigcup_{k=1,2}T_{{\rm HOR}k}(n,\mathbb R)$. Let $\operatorname{Sp}(S)$ and…

Let $T(n,\mathbb R)$ be the space of upper triangular matrices under consideration. A Seifert form stratum is a union of components of a fiber of the map to isomorphism classes of…