> _>> _> k])})]}
(map (coefficient f x $) (between 0 m)))))
(define $coefficient
(lambda [$f $x $m]
(if (eq? m 0)
(/ (sum (match-all f math-expr
[
$ts)> _>> _>
(foldl *' a (map 2#(**' %1 %2) ts))]))
(denominator f))
(coefficient' f x m))))
(define $coefficient'
(lambda [$f $x $m]
(/ (sum (match-all f math-expr
[
> _>> _>
(if (eq? m k)
(foldl *' a (map 2#(**' %1 %2) ts))
0)]))
(denominator f))))