  We propose a (limited) solution to the problem of constructing stream values
defined by recursive equations that do not respect the guardedness condition.
The guardedness condition is imposed on definitions of corecursive functions in
Coq, AGDA, and other higher-order proof assistants. In this paper, we
concentrate in particular on those non-guarded equations where recursive calls
appear under functions. We use a correspondence between streams and functions
over natural numbers to show that some classes of non-guarded definitions can
be modelled through the encoding as structural recursive functions. In
practice, this work extends the class of stream values that can be defined in a
constructive type theory-based theorem prover with inductive and coinductive
types, structural recursion and guarded corecursion
