You can look on a depreciation worksheet or on your Form 8829, Line 42.
"42 Depreciation allowable (see instructions). Multiply line 40 by line 41. Enter here and on line 30 above."
You will have to do some math or look back at every Form 8829 to see if it was taken.
Regardless of whether you actually took it each year or not, it has to be recaptured.
