We endow the set of isomorphic classes of matroids with a new Hopf algebra structure, in which the coproduct is implemented via the combinatorial operations of restriction and deletion. We also initiate the investigation of dendriform coalgebra structures on matroids and introduce a monomial invariant which satisfy a convolution identity with respect to restriction and deletion.
图或拟阵的Tutte多项式，以W. T. Tutte具有重要的泛性质，即任何具有删除和收缩约简的乘法图或网络不变量都必须是它的求值。删除和收缩操作是许多网络模型的自然约简，这些网络模型产生于计算机科学、工程、优化、物理和生物学的核心问题。尽管不变量一般来说是P-难以计算的，但在很多情况下，我们面临着计算某些图族或拟阵族的Tutte多项式的任务。在这项工作中，我们编译已知的Tutte多项式的一些家庭的图形和拟阵的公式。此外，我们给出了用于找到公式的技术的简要说明。希望这对组合数学和其他领域的研究人员有用。
Las Vergnas多项式是Tutte多项式到胞腔嵌入图的扩展。它是由Michel Las Vergnas在1978年引入的，作为拟阵态射的Tutte多项式的特例。虽然一般的Tutte多项式的态射拟阵有一套完整的删除-收缩关系，其专门细胞嵌入图没有。在这里，我们扩展Las Vergnas多项式的伪曲面图。我们表明，在这种设置中，我们可以定义删除和收缩嵌入图一致的删除和收缩的基本拟阵的角度来看，从而产生一个版本的拉斯维加斯Vergnas多项式完整的递归定义。这也使我们能够更深入地了解Las Vergnas多项式，Bollobas-Riordan多项式和Krushkal多项式之间的关系。我们也借此机会扩展一些拉斯维加斯Vergnas的结果欧拉电路从图表面的低亏格表面的任意亏格。
Brown has shown that the Stanley-Reisner ring of the broken circuit complex of a graph has a linear system of parameters which is defined in terms of the circuits and cocircuits of the graph. Later on Brown and Sagan conjectured a special set of monomials - a so-called NBC basis - described in terms of the circuits and cocircuits of the graph to be a monomial basis for the corresponding quotient of the Stanley-Reisner ring and proved this to be true for theta and phi graphs. We generalize the aforementioned linear system of parameters to broken circuit complexes of regular matroids and transfe…
By considering Tutte polynomials of Hopf algebras, we show how a Tutte polynomial can be canonically associated with combinatorial objects that have some notions of deletion and contraction. We show that several graph polynomials from the literature arise from this framework. These polynomials include the classical Tutte polynomial of graphs and matroids, Las Vergnas' Tutte polynomial of the morphism of matroids and his Tutte polynomial for embedded graphs, Bollobas and Riordan's ribbon graph polynomial, the Krushkal polynomial, and the Penrose polynomial. We show that our Tutte polynomials of…
In this work, we study matroids over a domain and several classical combinatorial and algebraic invariants related. We define their Grothendieck-Tutte polynomial $T_{\mathcal{M}}(x,y)$, extending the definition given by Fink and Moci in 2016, and we show that such polynomial has the classical deletion-contraction property. Moreover, we study the set of independencies for a realizable matroid over a domain, generalizing the definition of \emph{poset of torsions} $Gr(\mathcal{M})$ given by the second author in 2017. This is a union of identical simplicial posets as for (quasi-)arithmetic matroid…
