₅ within the recursive environment doesn't truncate decimals like other builtins that take integer arguments

[kcruijss]

Almost all 05AB1E builtins that require integer arguments, will truncate decimal values when given instead, which is a great feature. Unfortunately, ₅ a(x) (and ₆ a(n-x) as well) within the recursive environment doesn't seem to do this.

Try it online to reproduce.
Try it online with ï as workaround for the intended result.
Found in this codegolf answer of mine.