Is my answer the following question is correct:
Q: What is the augmented seventh from E?
A: D double sharp
Write down the note (of your choosing) on the bottom line of the treble staff which is E.
Note down the same note a generic seventh from above. This will be positioned on the second line of the staff which is D.
On a keyboard, count 12 half steps from E and you end up at E.
Thus an augmented seventh from E is D double sharp.