<qa>  What is the first dose of immunotherapy initiated after the first dose?This is an open-label, multicenter pilot Phase 1 study of the checkpoint antibodies ipilimumab and nivolumab in combination with radiotherapy in 18 subjects with unresectable stage IV melanoma. All subjects will receive concurrent ipilimumab 3 mgkg and nivolumab 1 mgkg every 3 weeks for 4 doses, followed by nivolumab monotherapy 3 mgkg every 2 weeks. Radiotherapy will be initiated after the first dose and before the second dose of immunotherapy. 