Breakpoint analysis and permutation codes in generalized Kendall tau and Cayley metrics

Permutation codes under the Cayley, Kendall tau, and Ulam metrics have been studied recently due to applications in flash memories. We consider permutation codes under more general metrics. We use breakpoints in permutations to gain additional insights to distances in codes. As a result, we construct codes under these general metrics that are larger than those previously known under more restricted metrics.