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Unique date's numbers come up

For most of us, it’s just another Wednesday, but for mathematicians and statisticians, today is a big day, full of numerical significance.

The date is 11-12-13 – and it’s the last time three consecutive numbers will line up in our lifetimes making it a day to remember for dedicated number crunchers. The next sequential number date is 1 February 2103 (1-2-03)


11-12-13 - the last time three consecutive numbers will line up in our lifetimes
Professor Sanju Velani from the Department of Mathematics at the University of York explained: “The sequential numbers make this date unusual, but of even more interest for number theorists is the fact that today’s date also features a twin prime pair: namely 11 and 13.  

“One of the oldest open challenges in mathematics is to prove there are infinitely many twin prime pairs – the notorious Twin Prime Conjecture.   Spectacular progress towards the conjecture has been made this year first by Yitang Zhang and then by James Maynard. The occurrence of a twin prime pair in a sequential number date is extremely rare – the next time it will occur will be 3 April, 2105 in 92 years time.”

Americans marked their own version of sequential number day last month on November 12 because of the different way they format the date. Thousands celebrated the statistical anomaly by getting married.

Professor Velani, is a member of the Number Theory group at York who have a particular interest in Diophantine Approximation, Random Matrix Theory and Transcendence Theory.   He said: “The former continues to play a significant role in applications to real-world problems including those in the rapidly developing areas of electronic communications, antenna design and signal processing.”

Further information

Find out more about the Department of Mathematics at the University of York