%This command provide the text about number theory in the first column %of the page 5 % %The command has one parameter: % 1) The width of the text \newcommand\TFiveNumberTheory[1]{% \parbox[t]{#1}{% \TFiveColOneFontSize %Space around math environments \DisplaySpace{\TFiveDisplaySpace}{\TFiveDisplayShortSpace} %The column is too narrow, ragged rigth is %nicer \raggedright \TFiveTitle{The Chinese remainder theorem:} There exists a number $C$ such that: \[ \begin{array}{l% @{\hspace{.1em}}c@{\hspace{.2em}}% l% c% l} C & \equiv& r_{1} & \bmod & m_{1} \\ & & & \vdots & \\ C & \equiv& r_{n} & \bmod & m_{n} \\ \end{array} \] if $m_{i}$ and $m_{j}$ are relatively prime for $i\neq j$. \TFiveTitle{Euler's function:} $\phi(x)$ is the number of positive integers less than $x$ relatively prime to $x$. If $\prod_{i=1}^n p^{e_i}_i$ is the prime factorization of $x$ then \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{\phi(x) = \prod_{i=1}^n p^{e_i - 1}_i (p_i - 1)} \end{DisplayFormulae} \TFiveTitle{Euler's theorem:} If $a$ and $b$ are relatively prime then \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{1 \equiv a^{\phi(b)} \bmod b} \end{DisplayFormulae} \TFiveTitle{Fermat's theorem:} \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{1 \equiv a^{p-1} \bmod p} \end{DisplayFormulae} \TFiveTitle{The Euclidean algorithm:} if $a > b$ are integers then \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{gcd(a, b) = \gcd(a \bmod b, b)} \end{DisplayFormulae} \AdjustSpace{1.5ex plus .5ex minus 1ex} If $\prod_{i=1}^n p^{e_i}_i$ is the prime factorization of $x$ then \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{S(x) = \sum_{d\vert x} d = \prod_{i=1}^n \frac{p^{e_i+1}_i - 1}{p_i - 1}} \end{DisplayFormulae} \TFiveTitle{Perfect Numbers:} $x$ is an even perfect number iff $x = 2^{n-1}(2^n - 1)$ and $2^n - 1$ is prime. \TFiveTitle{Wilson's theorem:} $n$ is a prime iff $(n-1)! \equiv -1 \bmod n$. \TFiveTitle{M\"obius inversion:} \mbox{$\mu(i) = \left\{\begin{array}{@{\hspace{.2em plus .05em minus .05em}}l% @{\hspace{.3em plus .05em minus .05em}}l} 1 & \text{if }i = 1 \\ 0 & \text{if $i$ is not square-free} \\ (-1)^r &\text{if $i$ is the product of} \\ &\text{$ir$ distinct primes.} \\ \end{array}\right.$} If $G(a) = \sum_{d \vert a} F(d)$ then $F(a) = \sum_{d \vert a} \mu(d) G\Big(\frac{a}{d}\Big)$ \TFiveTitle{Prime numbers:} \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} %Equation 1 \def\FirstPart{p_n =} \FmPartA{\FirstPart \ln n + n \ln \ln n - n + n \frac{\ln \ln n}{\ln n}+} \FmPartB{\FirstPart}{O\left(\frac{n}{\ln n}\right)} %Equation 2 \def\FirstPart{\pi(n) =} \FmPartA{\FirstPart\frac{n}{\ln n} + \frac{n}{(\ln n)^2} + \frac{2! n}{(\ln n)^3}+} \FmPartB{\FirstPart}{O\left(\frac{n}{(\ln n)^4}\right)} \end{DisplayFormulae} } }