Codes Correcting a Single Long Duplication Error

We consider the problem of constructing a code capable of correcting a single long tandem duplication error of variable length. As the main contribution of this paper, we present an efficiently encodable code of length n + 1 and redundancy 1 that can correct a single duplication of length at least K = 4•⌈logn⌉+1. We also show that in the class of codes correcting a single long duplication with redundancy 1, the value K in our construction is order-optimal.