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\begin{abstract}
Suppose $c\geq 2$ and $d\geq 2$ are integers, and let $S$ be the set of
integers $\left\lfloor c^j/d^k\right\rfloor$, where $j$ and $k$ range
over the nonnegative integers.  Assume that $c$ and $d$ are multiplicatively
independent; that is,
if $p$ and $q$ are integers for which $c^p=d^q,$ then 
$p=q=0$.  The numbers in $S$ form interspersions in various ways.  Related
fractal sequences and permutations of the set of nonnegative integers are
also discussed.
\end{abstract}

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