Sudoku Checker and the Minimum Number of Clues Problem

1st January, 2012

Update:  We have solved the sudoku minimum number of clues problem.   We have verified by exhaustive computer search that a 16-clue puzzle does not exist.

For further details, please download Version 2 of our article and the source code of our programme checker.

The original version is here.

Gary McGuire



Take a look at our old page from 2006.


Graphic of the Wikipedia sudoku page traffic around 1st January, 2012

News Reports of This Result:

Nature
Sunday Times
BBC number of the year
CBS News
MIT Technology Review
New Scientist
The Irish Times
YouTube (over 750,000 views)
BBC
Irish Examiner
Scientific American
The Guardian
BoingBoing
American Scientist
ABC Television show Catalyst
Wired Magazine's Dr. Sudoku
The Journal
Daily Edge
scitechdaily
i-Programmer
ZME Science
io9
GeekOSystem
Computing Now
Physorg
Slashdot
UCD News
Computing Now
Sudokuwiki
Irish Daily Mail
MAA Focus Magazine

Italy:
Il Post
Wired
AGI
Newnoticie
Galileo
Nextme

France:
Le Monde
CNRS
Le Parisien
Pour La Science
trictrac

Spain:
Publico
La VanGuardia
Gaussianos
ABC
La Nueva Espagna
Que
El Punt Avui

Belgium:
Nieuwsblad
Standaard

Iran:
Khabar
Khabarfarsi
Degargoon
Hamvatansalam

Austria:
ORF
Der Standard

China:
WHKP
Scitech

Netherlands:
Volkskrant
Engineers Online

Canada:
Cyberpresse
Cyberpresse blog

Switzerland:
NZZ
Ticino

India:
Yahoo India
Silicon India

Germany:
Frankfurter Allgemeine Zeitung
Kölner Stadt-Anzeiger
Spektrum
Wissenschaft Aktuell
Süddeutsche Zeitung
GEO

Russia:
Lenta
Compulenta
Nauka21Vek
Diver-Sant

Japan

Greece

Argentina

Slovakia

Lithuania

Croatia

Indonesia

Ukraine

Denmark

Poland

South Korea

Estonia

Xi'an
Michael Trick blog
David Eppstein Comment
Gordon Royle Blog
Xi'an's Blog
Jason Rosenhouse Blog
Berkeley Science Review
Xander Henderson Blog
The Conversation
Oxford University Press Blog
Irish Independent
University of South Carolina News

Mentions of the Problem:
A blog
Mortgage News
Math Maths Discussion (from about 4:40)
Italian radio interview
reddit
comment