Instance fmapUnsized {A B} (f : A -> B) (g : G A) `{Unsized _ g} :
Unsized (fmap f g).
Instance fmapMonotonic
{A B} (f : A -> B) (g : G A) `{SizeMonotonic _ g} :
SizeMonotonic (fmap f g).

Lemma semSized_alt A (f : nat -> G A) (H : forall n, SizeMonotonic (f n))
(H' : forall n m s,  n <= m -> semGenSize (f n) s \subset semGenSize (f m) s) :
semGen (sized f) <--> \bigcup_n (semGen (f n)).