% For Headlines with math
\usepackage{bm}

% Display math.
\usepackage{amsmath}
\usepackage{mathtools}
\usepackage{amssymb}
\usepackage{ntheorem}
\usepackage{nicefrac}

%\usepackage{pxfonts}
\usepackage[scaled=0.945,largesc,looser]{newpxtext}%better than pxfonts...
\usepackage[scaled=0.945,bigdelims]{newpxmath}
\let\mathbb\vmathbb

\DeclareFontFamily{LMX}{npxexx}{}
\DeclareFontShape{LMX}{npxexx}{m}{n}{<-> s * [1.045] zplexx}{}
\DeclareFontShape{LMX}{npxexx}{b}{n}{<-> s * [1.045] zplbexx}{}
%\DeclareFontShape{LMX}{npxexx}{m}{n}{<-> s * [0.78] zplexx}{}
%\DeclareFontShape{LMX}{npxexx}{b}{n}{<-> s * [0.78] zplbexx}{}
\DeclareFontShape{LMX}{npxexx}{bx}{n}{<->ssub * npxexx/b/n}{}

%\usepackage[scaled=0.91]{XCharter}
%\usepackage[scaled=0.89,type1]{cabin}% sans serif
%\usepackage[charter,varbb,scaled=1.00,noxchvw]{newtxmath}

%\usepackage{libertine}
%\usepackage[libertine]{newtxmath}

% New enviroment for remarks.
\theoremstyle{break}
\newtheorem{bem}{Bemerkung}

% New commands for math operators.
% Binomial coefficients.
\renewcommand{\binom}[2]{
  \Bigl(
  \begin{matrix}
    #1 \\
    #2
  \end{matrix}
  \Bigr)
}
% Eulerien numbers, first order.
\newcommand{\eulerI}[2]{
  \Bigl\langle
  \begin{matrix}
    #1 \\
    #2
  \end{matrix}
  \Bigr\rangle
}
% Stirling numbers, first kind.
\newcommand{\stirlingI}[2]{
  \Bigl[
  \begin{matrix}
    #1 \\
    #2
  \end{matrix}
  \Bigr]
}
% Stirling numbers, second kind.
\newcommand{\stirlingII}[2]{
  \Bigl\{
  \begin{matrix}
    #1 \\
    #2
  \end{matrix}
  \Bigr\}
}
% Legendre symbol.
\newcommand{\legendre}[2]{
  \Bigl(
  \dfrac{#1}{#2}
  \Bigr)
}
% Expectation values.
\newcommand{\E}{\text{E}}
% Greates common divisor.
\newcommand{\ggT}{\text{ggT}}
% sign for negative values
\newcommand{\sign}{\scalebox{0.66}[1.0]{\( - \)}}
% absolute values
\newcommand{\abs}[1]{\left|#1\right|}
% ceiling function
\newcommand{\ceil}[1]{\left\lceil#1\right\rceil}
% floor function
\newcommand{\floor}[1]{\left\lfloor#1\right\rfloor}
% multiplication
\renewcommand{\*}{\ensuremath{\cdotp}}