wer bound of Ω(nlog2 n/(loglogn)2) for the worst-caserunningtimeofShellsortwithanyinputsequence (see also [11]) and Jiang et al. [23] establish a lower bound of Ω(pn1+1/p) for the average-case running time of Shellsort. Thus, the only way to achieve an O(nlogn) averagetime bound for Shellsort is to use an offset sequence of length Θ(logn), and, even then, the problem of proving an O(nlogn) average running-time bound for a version of Shellsort is a long-standing open problem [42].