From 0e4b2e9d268849fd9518471e85825fbd4e9711e8 Mon Sep 17 00:00:00 2001 From: Yu Cong Date: Thu, 4 Dec 2025 13:47:34 +0800 Subject: [PATCH] z --- main.tex | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/main.tex b/main.tex index 8febbe0..0f5834a 100644 --- a/main.tex +++ b/main.tex @@ -178,8 +178,10 @@ for any base $B$ of $M'$, the expected size of intersection is at most $O(k')$. A counterexample would be uniform matroids $U_{2n,n}$. The size of every $k'$-cocycle is $k'+n$, and for any $k'$-cocycle there are bases using $O(n)$ elements in the cocycle. -\paragraph{Nice properties} -$\cl(F+e)\setminus F$ is a partition of $E\setminus F$ for general matroids. +\begin{proposition} +Let $M=(E,\mathcal I)$ be a matroids and let $F$ be a flat of $M$. +Then $\cl(F+e)\setminus F$ is a partition of $E\setminus F$. +\end{proposition} \subsection{Support size} @@ -192,7 +194,7 @@ The strategy is to first find a $\geq k$-cocycle using the utilization algorithm Note that LP gives an ideal tree packing with $O(m)$ support size. \subsection{Rigidity matroids} -\begin{conjecture}\label{conj:idealrigidbase} +\begin{conjecture} Let $M$ be a connected 2D rigidity matroid on graph $G=(V,E)$. Let $F^*$ be the optimal flat for strength $F^*=\argmin_{F\subset E}\frac{c(E\setminus F)}{r(E)-r(F)}$. Let $X\subset E\setminus F^*$ be a independent set with rank $r(E)-r(F^*)$. Then for any maximal independent set $B_{F^*}\subset F^*$, $X\cup B_{F^*}$ is a base of $M$. \end{conjecture}