The information that is understood here can be included. Alternate translation: "and then he appeared to the twelve disciples" (See: [[rc://en/ta/man/jit/figs-ellipsis]])
Paul used the term "the twelve" to mean the original disciples, known as apostles, that followed Jesus. Although, when Jesus appeared to the apostles, Judas had already died, Paul still refers to the groups as "twelve." Alternate translation: "to the rest of the apostles" (See: [[rc://en/ta/man/jit/figs-explicit]])