HomeScienceFive 60-sided dice solve a 15-year quest for perfectly fair turn order

Five 60-sided dice solve a 15-year quest for perfectly fair turn order

At a gaming convention around 2010, board game designer James Ernest posed a deceptively simple challenge to his friend Eric Harshbarger: could a set of dice be built so that any number of players, each taking one die, would have exactly the same chance of rolling the highest number, with no ties or rerolls? That question launched a long, collaborative effort led by Eric Harshbarger, a mathematician at Auburn University, and supported by colleagues including Robert Ford. Over roughly 15 years they sought configurations that deliver equal odds not only for who goes first but for the full ordering of players.

The project produced smaller, practical solutions along the way. The team found a three-player arrangement distributed numbers 1–18 across three standard six-sided dice, and a four-player set using four 12-sided dice. In testing these designs the researchers uncovered a stronger property they call permutation fairness: every possible sequence of players is equally likely. During this phase Harshbarger produced and sold handcrafted sets and numerical patterns drew wider interest from hobbyists and educators. The work also connected with the mathematics and board games communities exploring fair randomization methods.

The five-player problem proved far more demanding because the space of possible number assignments explodes to astronomically large proportions. Brute-force search was infeasible, so the team looked for symmetries and structural shortcuts. In mid-2023 Canadian software engineer Paul Meyer identified a workable configuration: five 60-sided dice whose faces collectively carry the integers 1 through 300 with no repeats. Harshbarger verified the result; the arrangement satisfies the no-tie, no-reroll condition and preserves permutation fairness for any subset of players.

Beyond the mathematical achievement, the set meets practical aims: the dice are small enough to manufacture and usable in ordinary play. To celebrate the discovery and to draw public attention to abstract ideas, Harshbarger also carved five oversized wooden replicas from different woods; these sculptures are now installed in Auburn’s new math building. The team frames the project as an instance where an accessible puzzle led to deeper combinatorial structure, and where tangible objects help invite curiosity about dice and mathematical design.

Advertisementspot_imgspot_img

Hot this week

Counterfeit rush: how fake retatrutide is spreading ahead of approval

Counterfeit versions of retatrutide are appearing online and offline while the drug remains unapproved, raising safety and regulatory concerns.

After early exit, Fery says US Open debut showed him what to improve

Arthur Fery says his cut-short US Open debut clarified what he must work on as he reflects on the Grand Slam experience.

Roman Telescope Begins L2 Voyage to Map Dark Cosmos and Hunt Distant Worlds

NASA's Roman Space Telescope departs for L2 to survey dark matter, dark energy and exoplanets with unprecedented speed and data volume.

Ferry Capsizes Off Northern Cyprus: Eight Dead, Dozens Unaccounted For

A ferry carrying nearly 270 people overturned off northern Cyprus; eight dead and 18 missing as search and rescue continues.

Art Garfunkel, Restless Voice: Returning to the Stage at 83

At 83, Art Garfunkel resumes touring after a lengthy pause, reflecting on a varied life as singer, actor, teacher and voracious reader.

Counterfeit rush: how fake retatrutide is spreading ahead of approval

Counterfeit versions of retatrutide are appearing online and offline while the drug remains unapproved, raising safety and regulatory concerns.

Prepare now: Politician urges households to stock food ahead of this winter’s storms

Dame Angela Eagle urges households to stock essential supplies as a developing weather event may bring extreme storms this winter.

Private US Envoys Meet Putin in Moscow, Head to Ukraine for Further Talks

Jared Kushner and Steve Witkoff met Vladimir Putin in Moscow and plan to hold follow-up discussions in Ukraine as part of ongoing private diplomacy.

Burnham’s Moment: How a Resilient Reform UK Shapes the Centre-Left Agenda

Burnham’s early premiership opens space for policy moves, but Reform UK’s steady support constrains the centre-left’s path forward.

Osaka advances to fourth round as Jovic halts Eala’s surge at US Open

Naomi Osaka defeated Elise Mertens in three sets to reach the US Open fourth round, while Jovic ended Eala's surprise run.

Herzog Rejects ‘Neurodivergence’ Label as He Defends Outsider Figures

Werner Herzog criticized the term 'neurodivergence' at Venice, addressing readings of his monomaniacal protagonists and his latest film with the Mara sisters.

Planet-sized detector: Earth’s field tightens dark matter constraints and flags strange signals

Researchers used Earth's magnetic field and atmosphere as a detector, setting new limits on ultralight axions and finding unexplained dark photon signals.

How Developing Countries Can Achieve More With Fewer Resources

Strategies for resource-efficient development: fiscal reform, low-carbon tech, digitalization and stronger institutions to boost resilience.
Advertisementspot_img

Related Articles