\documentclass[12pt,ifthen]{article} \usepackage{amsmath} \usepackage{amssymb} \usepackage{html} \usepackage{hyperref} \usepackage{tikz} \newcommand{\PVDW}{{\rm PVDW}} \newcommand{\OBS}{{\rm D}} \newcommand{\D}{{\sf D}} \newcommand{\N}{{\sf N}} \newcommand{\Z}{{\sf Z}} \newcommand{\Q}{{\sf Q}} \newcommand{\R}{{\sf R}} \newcommand{\reals}{{\sf R}} \newcommand{\into}{{\rightarrow}} \newcommand{\ceil}[1]{\lceil #1 \rceil} \newcommand{\COL}{{\rm COL}} \newcommand{\fractional}{{\rm frac}} \usepackage{amsthm} \newtheorem{theorem}{Theorem} \begin{document} \centerline{\bf CMSC 752 Homework 12} \centerline{\bf Morally Due Tue April 29, 2025} \centerline{\bf Dead Cat May 1} \bigskip \newif{\ifshowsoln} \showsolntrue % comment out to NOT show solution inside \ifshowsoln and \fi blocks. \smallskip \begin{enumerate} \item (50 points) Let $k\in\N$. Show the following {\it $\forall c$ $\exists W=W(c)$ such that, $\forall$ $\COL\colon [W]\into [c]$ $\exists a,d$ such that $$a, a+d^2+d, a+d^2+2d, \ldots, a+d^2+kd$$ are all the same color.} You may assume VDW's theorem, which the cool kids call, $\PVDW(\omega)$. \newpage \item (50 points) Show the following {\it $\forall c$ $\exists W=W(c)$ such that, $\forall$ $\COL\colon [W]\into [c]$ $\exists a,d$ such that $$a, a+d^3$$ are all the same color.} You may assume $\PVDW(\omega,\omega)$. \end{enumerate} \end{document}