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In this thesis we introduce a new type of card shuffle called the one-sided transposition shuffle. At each step a card is chosen uniformly from the pack and then transposed with another card chosen uniformly from below it. This defines a…

Probability · Mathematics 2020-12-10 Oliver Matheau-Raven

We study the joint distribution of descents and sign for elements of the symmetric group and the hyperoctahedral group (Coxeter groups of types $A$ and $B$). For both groups, this has an application to riffle shuffling: for large decks of…

Combinatorics · Mathematics 2021-02-05 Jason Fulman , Gene B. Kim , Sangchul Lee , T. Kyle Petersen

We study the topdrop map, a mapping on permutations in $S_n$ related to card shuffling. We show this map is bijective and study its orbit structure. We introduce the notion of the topdrop-necklace as a way of classifying the orbits of the…

Combinatorics · Mathematics 2025-10-21 Nathan R. Krause

In the cyclic-to-random shuffle, we are given n cards arranged in a circle. At step k, we exchange the k'th card along the circle with a uniformly chosen random card. The problem of determining the mixing time of the cyclic-to-random…

Probability · Mathematics 2007-05-23 Elchanan Mossel , Yuval Peres , Alistair Sinclair

Data format reverse engineering commonly involves identifying conserved format motifs. However, this process typically requires establishing a common ordering for format elements across instances, particularly for formats using…

Information Theory · Computer Science 2020-03-03 Steve Huntsman

Normally a chess problem must have a unique solution, and is deemed unsound even if there are alternatives that differ only in the order in which the same moves are played. In an enumerative chess problem, the set of moves in the solution…

Combinatorics · Mathematics 2007-05-23 Noam D. Elkies

Consider the following one player game. A deck containing $m$ copies of $n$ different card types is shuffled uniformly at random. Each round the player tries to guess the next card in the deck, and then the card is revealed and discarded.…

Probability · Mathematics 2021-07-20 Sam Spiro

Various card tricks involve under-down dealing, where alternatively one card is placed under the deck and the next card is dealt. We study how the cards need to be prepared in the deck to be dealt in order. The order in which the $N$ cards…

In the top to random shuffle, the first a cards are removed from a deck of n cards 12 \cdots n and then inserted back into the deck. This action can be studied by treating the top to random shuffle as an element B_a, which we define…

Combinatorics · Mathematics 2016-12-20 Roger Tian

Analogues of 1-shuffle elements for complex reflection groups of type $G(m,1,n)$ are introduced. A geometric interpretation for $G(m,1,n)$ in terms of rotational permutations of polygonal cards is given. We compute the eigenvalues, and…

Combinatorics · Mathematics 2018-11-14 O. Ogievetsky , V. Petrova

The well-known Gilbert-Shannon-Reeds model for riffle shuffles assumes that the cards are initially cut 'about in half' and then riffled together. We analyze a natural variant where the initial cut is biased. Extending results of Fulman…

Probability · Mathematics 2011-12-13 Sami Assaf , Persi Diaconis , Kannan Soundararajan

In a well-shuffled deck of cards, what is the probability that somewhere in the deck there are adjacent cards of the same rank? What is the average number of adjacent matches? What is the probability distribution for the number of matches?…

Combinatorics · Mathematics 2025-01-15 Kent E. Morrison

Inspired by a common technique for shuffling a deck of cards on a table without riffling, we continue the study of a prequel paper on the pile shuffle and its capabilities as a sorting device. We study two sort feasibility problems of…

Computational Complexity · Computer Science 2025-06-09 Kyle B. Treleaven

We show that any permutation of ${1,2,...,N}$ can be written as the product of two involutions. As a consequence, any permutation of the elements of an array can be performed in-place in parallel in time O(1). In the case where the…

Data Structures and Algorithms · Computer Science 2015-03-20 Qingxuan Yang , John Ellis , Khalegh Mamakani , Frank Ruskey

We present a version of the domino shuffling algorithm (due to Elkies, Kuperberg, Larsen and Propp) which works on a different lattice: the hexagonal lattice superimposed on its dual graph. We use our algorithm to count perfect matchings on…

Combinatorics · Mathematics 2011-10-25 Cyndie Cottrell , Benjamin Young

We develop a combinatorial and order-theoretic framework for shuffles, understood as ordered concatenations of indexed families of sequences that induce total orders on the natural numbers. Motivated by the classical \v{S}arkovski\u{i}…

Combinatorics · Mathematics 2026-02-03 João Dias , Bruno Dinis , Carlos Correia Ramos

A permutation statistic $\operatorname{st}$ is said to be shuffle-compatible if the distribution of $\operatorname{st}$ over the set of shuffles of two disjoint permutations $\pi$ and $\sigma$ depends only on $\operatorname{st}\pi$,…

Combinatorics · Mathematics 2023-09-29 Jinting Liang , Bruce E. Sagan , Yan Zhuang

The Thorp shuffle is defined as follows. Cut the deck into two equal piles. Drop the first card from the left pile or the right pile according to the outcome of a fair coin flip; then drop from the other pile. Continue this way until both…

Probability · Mathematics 2007-05-23 Ben Morris

We study sorting by queues that can rearrange their content by applying permutations from a predefined set. These new sorting devices are called shuffle queues and we investigate those of them corresponding to sets of permutations defining…

Combinatorics · Mathematics 2022-07-05 Stoyan Dimitrov

Permutation puzzles, such as the Rubik's Cube and the 15 puzzle, are enjoyed by the general public and mathematicians alike. Here we introduce quantum versions of permutation puzzles where the pieces of the puzzles are replaced with…

Quantum Physics · Physics 2025-04-16 Noah Lordi , Maedee Trank-Greene , Akira Kyle , Joshua Combes