%Plain TeX -> abstract for V4(2) R12
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\noindent {\bf Kevin Keating and Jonathan L.~King }
\bigskip\noindent Shape Tiling
\vskip.5cm\noindent 
  Given a list $1\times 1, 1\times a, 1\times b, \dots, 1\times c$ of 
rectangles, with~$a,b,\dots,c$ non-negative, when can~$1\times{t}$ 
be tiled by positive and negative copies of rectangles which are 
similar (uniform scaling) to those in the list? We prove that such
 a tiling exists  iff\  $t$~is in the field~$Q(a,b,\dots,c)$.

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