A person was required to take minimum distributions but did not do so. That same person paid the 50% excise tax. Must that person now withdraw the required amounts he should have previously taken out and begin RMD's based on the remaining account balance? Or can that person now calculate RMD on the full account?
Cites would be helpful.

The regulations under Treas. Reg. 1.401(a)(9)-1 don't answer your questions (but see 1.401(a)(9)-1, Q&A F-5). The answer to your questions are in Rev. Proc. 98-22, Appendix A .06 (EPCRS correction principles)