\documentclass[compress, 9pt, german, t]{beamer}
\usepackage{etex}

\usepackage[english]{babel}
\uselanguage{English}
\languagepath{English}

\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage{arev}
\usepackage{mathpazo}
\usepackage{microtype}

\usepackage{url}
\usepackage{listings}
\usepackage{xcolor}
\usepackage{tabu}
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat=1.8}
\usetikzlibrary{automata}
\usetikzlibrary{calc}
\usetikzlibrary{shapes}
\usetikzlibrary{positioning}
\usetikzlibrary{chains}

\usepackage{amsmath}
\usepackage{mathdots}
\usepackage{mathtools}
\mathtoolsset{showonlyrefs,showmanualtags}
\usepackage{mathrsfs}
\usepackage{csquotes}

\usepackage{todonotes}

\usepackage{beamerthemeLEA2}
\setbeamercovered{transparent}

\newcommand{\N}{\mathbb{N}}
\newcommand{\Z}{\mathbb{Z}}
\newcommand{\Q}{\mathbb{Q}}
\newcommand{\R}{\mathbb{R}}
\newcommand{\C}{\mathbb{C}}
\newcommand{\Prob}{\mathrm{P}}
\newcommand{\Oh}{\mathcal{O}}

\newcommand{\abs}[1]{\left\vert #1 \right\vert}
\newcommand{\powerset}[1]{\mathcal{P}\left( #1 \right)}
\newcommand{\setnot}[1]{\overline{#1}}
\newcommand{\setsymdiff}{\,\triangle\,}

\newcommand{\defeq}{\coloneqq} %Mathtools already defines this

\pgfdeclarelayer{background}
\pgfdeclarelayer{foreground}
\pgfsetlayers{background,main,foreground}

\tikzstyle{edge} = [draw,very thick,->,>=latex]
\tikzstyle{pretty} = [circle,thick,draw,fill=tumblue!10]
\tikzstyle{every edge} = [edge]
\tikzstyle{every state} = [pretty]
\tikzstyle{automaton} = [shorten >=1pt, node distance = 3cm, auto, bend angle=20, initial text=]
\tikzstyle{small} = [every node/.style={scale=0.5}, baseline=(current bounding box.north), font=\Huge]