What do the codes mean in Box 17 of the K-1 for partnerships?

Alternative minimum tax (AMT) items
A: Post-1986 depreciation adjustment
B: Adjusted gain or loss
C: Depletion (other than oil & gas)
D: Oil, gas, & geothermal--gross income *
E: Oil, gas, & geothermal--deductions *
F: Other AMT items *

* Not supported

See the Schedule K-1 (Form 1065) instructions  for more info about these codes.