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\begin{document}
\fontsize{97}{0}\selectfont
\noindent%\color{grey}
\decreasingdigits{$\pi=$}{3}{14159265% 8
35897932384626% 14
433832795028841% 15
9716939937510582% 16
09749445923078164% 17
0628620899862803482% 19
53421170679821480865% 20
13282306647093844609550% 23
5822317253594081284811174% 25
50284102701938521105559644622% 29
9489549303819644288109756659334461% 34
28475648233786783165271201909145648566923% 41
460348610454326648213393607260249141273724587006606% 51
31558817488152092096282925409171536436789259036001133053054882046652% 68
1384146951941511609433057270365759591953092186117381932611793105118548074462379962749567351885752724891227% 106 = 486 sofar
93818301194912983367336244065664308602139494639522473719070217986094370277053921717629317675238467481846766940513200056812714526356082778577134275778960917363717872146844090122495343014654958537105079227968925892354201995611212902196086403441815981362977477130996051870721134999999837297804995105973173281609631859502445945534690830264252230825334468} %350
%50352619311881710100031378387528865875332083814206171776691473035982534904287554687311595628638823537875937519577818577805321712268066130019278766111959092164201989380952572010654858632788659361533818279682303019520353018529689957736225994138912497217752834791315155748572424541506959508295331168617278558890750983817546374649393192550604009277016711390098488240}
\begin{center}\tiny 
How to print an infinite decimal expansion in a finite space --- 
...51\textbf{3} is the 600th digit ---
Math Poster 2007 --- Peter Jipsen --- Chapman University --- math.chapman.edu
\end{center}
\end{document}