A288970 Number of key comparisons to sort all n! permutations of n elements by the optimal trial-pivot quicksort.

0, 0, 2, 16, 112, 848, 7032, 64056, 639888, 6974928, 82531296, 1054724256, 14487894144, 212971227264

Offset

0,3

Comments

The 3 pivot elements are chosen from fixed indices (e.g., the last 3 elements). The "optimal" strategy minimizes, after the choice of the pivots is done, the expected partitioning cost.

Links

Table of n, a(n) for n=0..13.

M. Aumüller and M. Dietzfelbinger, How Good Is Multi-Pivot Quicksort?, ACM Transactions on Algorithms (TALG), Volume 13 Issue 1, 2016.

M. Aumüller and M. Dietzfelbinger, How Good Is Multi-Pivot Quicksort?, arXiv:1510.04676 [cs.DS], 2016.

Daniel Krenn, Quickstar, Program in SageMath, on GitHub.

Index entries for sequences related to sorting.

Crossrefs

Cf. A001768, A003070, A036604, A117627, A117628, A159324, A288964, A288965, A288971.

Sequence in context: A117627 A117628 A288971 * A037564 A361743 A125725

Adjacent sequences: A288967 A288968 A288969 * A288971 A288972 A288973

Keyword

nonn,more

Author

Daniel Krenn, Jun 20 2017

Extensions

a(9)-a(11) from Melanie Siebenhofer, Jan 29 2018

a(12)-a(13) from Melanie Siebenhofer, Feb 02 2018

Status

approved