<html><head><meta name="color-scheme" content="light dark"></head><body><pre style="word-wrap: break-word; white-space: pre-wrap;">\def\startposition{
\inifulldiagram
\gofontsize{10}
\pos{d}{5}=\black{.}
\pos{d}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{4}=\black{.}
\centerline{\showfulldiagram}\caption{Othello start position}
}

\def\cornerpositions{
\inifulldiagram
\gofontsize{10}
\pos{b}{2}=\neutral{65}
\pos{b}{7}=\neutral{65}
\pos{g}{2}=\neutral{65}
\pos{g}{7}=\neutral{65}
\pos{a}{2}=\neutral{66}
\pos{a}{7}=\neutral{66}
\pos{b}{1}=\neutral{66}
\pos{b}{8}=\neutral{66}
\pos{g}{8}=\neutral{66}
\pos{g}{1}=\neutral{66}
\pos{h}{7}=\neutral{66}
\pos{h}{2}=\neutral{66}
\centerline{\showfulldiagram}\caption{Special positions around the corners} \label{cornerpositions}
}

\def\makingamove{
\inifulldiagram
\gofontsize{10}
\pos{d}{5}=\black{.}
\pos{d}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{4}=\black{.}
\pos{c}{4}=\neutral{65}
\pos{d}{3}=\neutral{65}
\pos{e}{6}=\neutral{65}
\pos{f}{5}=\neutral{65}
\centerline{\showfulldiagram}\caption{Black can place his first stone at these
places}\label{makingamove}
}

\def\validmoves{
\inifulldiagram
\gofontsize{10}
\pos{d}{5}=\black{.}
\pos{d}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{4}=\black{.}
\pos{d}{3}=\black{.}
\pos{c}{3}=\white{.}
\centerline{\showfulldiagram}\label{validmoves}\caption{Opening
c4,c3}
}

\def\fliponlyonce{
\inifulldiagram \gofontsize{10} \pos{c}{3}=\white{.}
\pos{d}{3}=\white{.} \pos{e}{3}=\white{.} \pos{f}{3}=\white{.}
\pos{f}{4}=\white{.} \pos{f}{5}=\white{.} \pos{f}{6}=\white{.}
\pos{e}{6}=\white{.} \pos{d}{6}=\white{.} \pos{c}{6}=\white{.}
\pos{d}{4}=\black{.} \pos{e}{4}=\black{.} \pos{d}{5}=\black{.}
\pos{e}{5}=\black{.}
\centerline{\showfulldiagram}\caption{Stones do not flip recursively}\label{fliponlyonce} }

\def\stablestones{
\inifulldiagram \gofontsize{10} \pos{a}{1}=\black{.}
\pos{b}{1}=\black{.} \pos{a}{2}=\black{.} \pos{a}{3}=\black{.}
\pos{b}{2}=\black{.} \pos{a}{4}=\black{.} \pos{h}{1}=\white{.}
\pos{h}{2}=\white{.} \pos{g}{1}=\white{.} \pos{g}{2}=\white{.}
\pos{g}{3}=\white{.} \pos{h}{3}=\white{.} \pos{f}{1}=\white{.}
\centerline{\showfulldiagram}\caption{Example of stable
stones}\label{stablestones} }

\def\maximumdisk{
\inifulldiagram
\gofontsize{10}
\pos{a}{3}=\white{.}
\pos{a}{4}=\white{.}
\pos{a}{5}=\white{.}
\pos{a}{6}=\white{.}
\pos{b}{3}=\white{.}
\pos{b}{4}=\white{.}
\pos{b}{5}=\white{.}
\pos{b}{6}=\white{.}
\pos{c}{1}=\white{.}
\pos{c}{2}=\white{.}
\pos{c}{3}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{c}{6}=\white{.}
\pos{c}{7}=\white{.}
\pos{c}{8}=\white{.}
\pos{d}{1}=\white{.}
\pos{d}{2}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{4}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\white{.}
\pos{d}{7}=\white{.}
\pos{d}{8}=\white{.}
\pos{e}{1}=\white{.}
\pos{e}{2}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{6}=\white{.}
\pos{e}{7}=\white{.}
\pos{e}{8}=\white{.}
\pos{f}{1}=\white{.}
\pos{f}{2}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\pos{f}{6}=\white{.}
\pos{f}{7}=\white{.}
\pos{f}{8}=\white{.}
\pos{g}{3}=\white{.}
\pos{g}{4}=\white{.}
\pos{g}{5}=\white{.}
\pos{g}{6}=\white{.}
\pos{h}{3}=\white{.}
\pos{h}{4}=\white{.}
\pos{h}{5}=\white{.}
\pos{h}{6}=\white{.}
\centerline{\showfulldiagram}\caption{Maximum disk strategy: black to play and win (46-18)}\label{maximumdisk}
}

\def\stabledisks{
\inifulldiagram \gofontsize{10} \pos{a}{1}=\white{.}
\pos{a}{2}=\white{.} \pos{a}{3}=\white{.} \pos{a}{4}=\white{.}
\pos{a}{5}=\white{.} \pos{a}{6}=\white{.} \pos{b}{1}=\white{.}
\pos{b}{2}=\white{.} \pos{b}{3}=\white{.} \pos{b}{4}=\white{.}
\pos{b}{5}=\white{.} \pos{b}{6}=\white{.} \pos{c}{1}=\white{.}
\pos{c}{2}=\white{.} \pos{c}{3}=\white{.} \pos{c}{4}=\white{.}
\pos{c}{5}=\white{.} \pos{c}{6}=\white{.} \pos{c}{7}=\white{.}
\pos{c}{8}=\white{.} \pos{d}{1}=\white{.} \pos{d}{2}=\white{.}
\pos{d}{3}=\white{.} \pos{d}{4}=\black{.} \pos{d}{5}=\black{.}
\pos{d}{6}=\white{.} \pos{d}{7}=\white{.} \pos{d}{8}=\white{.}
\pos{e}{1}=\white{.} \pos{e}{2}=\white{.} \pos{e}{3}=\white{.}
\pos{e}{4}=\white{.} \pos{e}{5}=\white{.} \pos{e}{6}=\white{.}
\pos{e}{7}=\white{.} \pos{e}{8}=\white{.} \pos{f}{1}=\white{.}
\pos{f}{2}=\white{.} \pos{f}{3}=\white{.} \pos{f}{4}=\white{.}
\pos{f}{5}=\white{.} \pos{f}{6}=\white{.} \pos{f}{7}=\white{.}
\pos{f}{8}=\white{.} \pos{g}{3}=\white{.} \pos{g}{4}=\white{.}
\pos{g}{5}=\white{.} \pos{g}{6}=\white{.} \pos{h}{3}=\white{.}
\pos{h}{4}=\white{.} \pos{h}{5}=\white{.} \pos{h}{6}=\white{.}
\centerline{\showfulldiagram}\caption{Examples of stable disks in an end game}\label{stabledisks} }



\def\quietmove{\inifulldiagram
\gofontsize{10}
\pos{b}{5}=\black{.}
\pos{c}{2}=\black{.}
\pos{d}{2}=\black{.}
\pos{e}{2}=\black{.}
\pos{f}{2}=\black{.}
\pos{f}{3}=\black{.}
\pos{g}{3}=\black{.}
\pos{g}{4}=\black{.}
\pos{b}{3}=\white{.}
\pos{b}{4}=\white{.}
\pos{c}{3}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{4}=\white{.}
\pos{d}{5}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{5}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\pos{g}{5}=\white{.}
\centerline{\showfulldiagram}\caption{Example of a quiet move}\label{quietmove}}

\def\frontiermovetwo{\inifulldiagram
\gofontsize{10}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{c}{2}=\black{.}
\pos{c}{3}=\black{.}
\pos{d}{2}=\black{.}
\pos{d}{3}=\black{.}
\pos{e}{2}=\black{.}
\pos{e}{3}=\black{.}
\pos{f}{3}=\black{.}
\pos{f}{4}=\black{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{d}{4}=\white{.}
\pos{d}{5}=\white{.}
\pos{e}{4}=\white{.}
\pos{e}{5}=\white{.}
\centerline{\showfulldiagram}\caption{}\label{frontiermovetwo}}

\def\frontierstones{\inifulldiagram
\gofontsize{10}
\pos{b}{3}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{4}=\black{.}
\pos{d}{3}=\black{.}
\pos{d}{4}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{d}{7}=\black{.}
\pos{e}{3}=\black{.}
\pos{e}{4}=\black{.}
\pos{e}{5}=\black{.}
\pos{f}{3}=\black{.}
\pos{f}{4}=\black{.}
\pos{f}{5}=\black{.}
\pos{b}{4}=\white{.}
\pos{b}{5}=\white{.}
\pos{c}{5}=\white{.}
\pos{c}{6}=\white{.}
\pos{c}{7}=\white{.}
\pos{e}{6}=\white{.}
\pos{e}{7}=\white{.}
\pos{f}{6}=\white{.}
\centerline{\showfulldiagram}\caption{Frontiers in the beginning of the game}\label{frontierstones}}

\def\mobilityexampletwo{\inifulldiagram
\gofontsize{10}
\pos{a}{4}=\black{.}
\pos{b}{3}=\black{.}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{6}=\black{.}
\pos{d}{3}=\black{.}
\pos{d}{4}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{3}=\black{.}
\pos{e}{4}=\black{.}
\pos{e}{5}=\black{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\centerline{\showfulldiagram}\caption{White to play and win a corner}\label{mobilityexampletwo}}

\def\mobiuitween{\inifulldiagram
\gofontsize{10}
\pos{a}{4}=\white{.}
\pos{b}{3}=\black{.}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{6}=\black{.}
\pos{d}{3}=\black{.}
\pos{d}{4}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{3}=\black{.}
\pos{e}{4}=\black{.}
\pos{e}{5}=\black{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{b}{7}=\black{.}
\pos{a}{2}=\white{.}
\pos{a}{3}=\white{.}
\pos{a}{7}=\white{.}
\pos{a}{5}=\white{.}
\pos{a}{6}=\white{.}
\centerline{\showfulldiagram}\caption{}\label{mobiuitween}}

\def\frontiermoveone{\inifulldiagram
\gofontsize{10}
\pos{a}{2}=\black{.}
\pos{b}{3}=\black{.}
\pos{c}{1}=\black{.}
\pos{c}{2}=\black{.}
\pos{d}{1}=\black{.}
\pos{d}{2}=\black{.}
\pos{e}{1}=\black{.}
\pos{e}{2}=\black{.}
\pos{f}{1}=\black{.}
\pos{f}{2}=\black{.}
\pos{a}{4}=\white{.}
\pos{a}{5}=\white{.}
\pos{a}{6}=\white{.}
\pos{a}{7}=\white{.}
\pos{b}{4}=\white{.}
\pos{b}{5}=\white{.}
\pos{b}{6}=\white{.}
\pos{b}{8}=\white{.}
\pos{c}{3}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{c}{6}=\white{.}
\pos{c}{7}=\white{.}
\pos{c}{8}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{4}=\white{.}
\pos{d}{5}=\white{.}
\pos{d}{6}=\white{.}
\pos{d}{7}=\white{.}
\pos{d}{8}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{6}=\white{.}
\pos{e}{7}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\pos{f}{6}=\white{.}
\pos{f}{7}=\white{.}
\centerline{\showfulldiagram}\caption{Frontier moves: h6 is devastating for black}\label{frontiermoveone}
}

\def\wedge{
\inifulldiagram
\gofontsize{10}
\pos{a}{2}=\black{.}
\pos{a}{3}=\black{.}
\pos{a}{4}=\black{.}
\pos{a}{5}=\black{.}
\pos{a}{6}=\black{.}
\pos{b}{1}=\black{.}
\pos{b}{3}=\black{.}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{c}{1}=\black{.}
\pos{c}{2}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{6}=\black{.}
\pos{d}{2}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{1}=\black{.}
\pos{e}{2}=\black{.}
\pos{e}{4}=\black{.}
\pos{f}{1}=\black{.}
\pos{g}{1}=\black{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{4}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{6}=\white{.}
\pos{f}{2}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\centerline{\showfulldiagram}\caption{White plays a4, wedging the first column}\label{wedge}}

\def\wedgetwo{\inifulldiagram
\gofontsize{10}
\pos{a}{3}=\black{.}
\pos{a}{4}=\black{.}
\pos{a}{5}=\black{.}
\pos{a}{6}=\black{.}
\pos{a}{7}=\black{.}
\pos{b}{1}=\black{.}
\pos{b}{3}=\black{.}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{c}{1}=\black{.}
\pos{c}{2}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{6}=\black{.}
\pos{d}{1}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{1}=\black{.}
\pos{e}{4}=\black{.}
\pos{f}{1}=\black{.}
\pos{f}{2}=\black{.}
\pos{g}{1}=\black{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{d}{2}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{4}=\white{.}
\pos{e}{2}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{6}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\centerline{\showfulldiagram}\caption{Wedging by sacrificing a corner}\label{wedgetwo}
}

\def\tempo{
\inifulldiagram
\gofontsize{10}
\pos{b}{3}=\black{.}
\pos{b}{4}=\black{.}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{c}{2}=\black{.}
\pos{c}{3}=\black{.}
\pos{c}{6}=\black{.}
\pos{d}{2}=\black{.}
\pos{d}{4}=\black{.}
\pos{d}{5}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{2}=\black{.}
\pos{e}{4}=\black{.}
\pos{e}{5}=\black{.}
\pos{e}{6}=\black{.}
\pos{f}{2}=\black{.}
\pos{f}{6}=\black{.}
\pos{a}{3}=\white{.}
\pos{a}{4}=\white{.}
\pos{a}{5}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{d}{3}=\white{.}
\pos{e}{3}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\centerline{\showfulldiagram}\caption{White to move: gaining tempo}\label{tempo}
}

\def\parity{
\inifulldiagram
\gofontsize{10}
\pos{b}{5}=\black{.}
\pos{b}{6}=\black{.}
\pos{d}{4}=\black{.}
\pos{d}{6}=\black{.}
\pos{e}{3}=\black{.}
\pos{e}{5}=\black{.}
\pos{f}{2}=\black{.}
\pos{f}{4}=\black{.}
\pos{g}{1}=\black{.}
\pos{g}{6}=\black{.}
\pos{a}{3}=\white{.}
\pos{a}{4}=\white{.}
\pos{a}{5}=\white{.}
\pos{a}{6}=\white{.}
\pos{a}{7}=\white{.}
\pos{b}{1}=\white{.}
\pos{b}{3}=\white{.}
\pos{b}{4}=\white{.}
\pos{c}{1}=\white{.}
\pos{c}{2}=\white{.}
\pos{c}{3}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{5}=\white{.}
\pos{c}{6}=\white{.}
\pos{c}{7}=\white{.}
\pos{c}{8}=\white{.}
\pos{d}{1}=\white{.}
\pos{d}{2}=\white{.}
\pos{d}{3}=\white{.}
\pos{d}{5}=\white{.}
\pos{d}{7}=\white{.}
\pos{d}{8}=\white{.}
\pos{e}{1}=\white{.}
\pos{e}{2}=\white{.}
\pos{e}{4}=\white{.}
\pos{e}{6}=\white{.}
\pos{e}{7}=\white{.}
\pos{e}{8}=\white{.}
\pos{f}{1}=\white{.}
\pos{f}{3}=\white{.}
\pos{f}{5}=\white{.}
\pos{f}{6}=\white{.}
\pos{f}{7}=\white{.}
\pos{f}{8}=\white{.}
\pos{g}{2}=\white{.}
\pos{g}{3}=\white{.}
\pos{g}{4}=\white{.}
\pos{g}{5}=\white{.}
\pos{g}{8}=\white{.}
\pos{h}{1}=\white{.}
\pos{h}{2}=\white{.}
\pos{h}{3}=\white{.}
\pos{h}{4}=\white{.}
\pos{h}{5}=\white{.}
\pos{h}{6}=\white{.}
\pos{h}{7}=\white{.}
\centerline{\showfulldiagram}\caption{Black to play and win}\label{parity}}

\def\paritytwo{
\inifulldiagram
\gofontsize{10}
\pos{c}{5}=\black{.}
\pos{c}{7}=\black{.}
\pos{d}{1}=\black{.}
\pos{d}{2}=\black{.}
\pos{d}{3}=\black{.}
\pos{d}{4}=\black{.}
\pos{e}{1}=\black{.}
\pos{e}{2}=\black{.}
\pos{f}{2}=\black{.}
\pos{f}{3}=\black{.}
\pos{f}{6}=\black{.}
\pos{f}{8}=\black{.}
\pos{g}{3}=\black{.}
\pos{g}{4}=\black{.}
\pos{g}{5}=\black{.}
\pos{g}{8}=\black{.}
\pos{h}{3}=\black{.}
\pos{h}{4}=\black{.}
\pos{h}{5}=\black{.}
\pos{h}{6}=\black{.}
\pos{h}{7}=\black{.}
\pos{h}{8}=\black{.}
\pos{a}{2}=\white{.}
\pos{a}{3}=\white{.}
\pos{a}{4}=\white{.}
\pos{a}{5}=\white{.}
\pos{a}{6}=\white{.}
\pos{a}{7}=\white{.}
\pos{a}{8}=\white{.}
\pos{b}{3}=\white{.}
\pos{b}{4}=\white{.}
\pos{b}{5}=\white{.}
\pos{b}{6}=\white{.}
\pos{b}{7}=\white{.}
\pos{b}{8}=\white{.}
\pos{c}{1}=\white{.}
\pos{c}{2}=\white{.}
\pos{c}{3}=\white{.}
\pos{c}{4}=\white{.}
\pos{c}{6}=\white{.}
\pos{c}{8}=\white{.}
\pos{d}{5}=\white{.}
\pos{d}{6}=\white{.}
\pos{d}{7}=\white{.}
\pos{d}{8}=\white{.}
\pos{e}{3}=\white{.}
\pos{e}{4}=\white{.}
\pos{e}{5}=\white{.}
\pos{e}{6}=\white{.}
\pos{e}{7}=\white{.}
\pos{e}{8}=\white{.}
\pos{f}{1}=\white{.}
\pos{f}{4}=\white{.}
\pos{f}{5}=\white{.}
\pos{f}{7}=\white{.}
\pos{g}{6}=\white{.}
\centerline{\showfulldiagram}\caption{Black to play and draw}\label{paritytwo}}

\def\overviewboard{
\inifulldiagram
\gofontsize{10}
\pos{d}{5}=\black{.}
\pos{d}{4}=\white{.}
\pos{e}{5}=\white{23}
\pos{e}{4}=\black{62}
\pos{d}{3}=\neutral{43}
\pos{b}{2}=\neutral{65}
\pos{b}{1}=\neutral{66}
\centerline{\showfulldiagram}\caption{All possible characters using  the Othello package}
}

\def\overviewboardcorner{
\inifulldiagram
\gofontsize{10}
\pos{d}{5}=\black{.}
\pos{d}{4}=\white{.}
\pos{e}{5}=\white{23}
\pos{e}{4}=\black{62}
\pos{d}{3}=\neutral{43}
\pos{b}{2}=\neutral{65}
\pos{b}{1}=\neutral{66}
\centerline{\showdiagram a-d:1-4 }\caption{The northwest corner of the overview board}
}
</pre></body></html>