A “Linear Value” is of the form:
the seventh value assigned to the variable a[382] since the call of the routine.
These values are ordered in time and the proof is by induction forward in time. Each value is produced either by copying such a value or as a complex arithemetic operation that yields linear combinations from linear combinations. Note that “the sixth” value that identifier b takes on is a complex constant.

You may consider the two varibles spelled “t” to be the same or different according to your taste.