Saturday, December 13, 2014

12-13-14, the last sequential day of the century

Jessica Contrera of The Washington Post has the story in On 12/13/14 one last chance to indulge in sequential date frenzy — this century, anyway.
It’s the very last sequential day of the century. We are already out of triple dates, the 11/11/11s and 12/12/12s, and Saturday we run out of 1/2/03s and 4/5/06s.

There is no 13/14/15! And there won’t be anything like it until the year 2101!
Journalists have been reporting on these special dates — calling wedding planners and casinos and numerologists and “scientists” — and maybe exaggerating the details of the situation a bit, but we’ll get to that — for 14 years.

So to celebrate this century’s last hurrah, this final quirk of the calendar, let us compile all the essential ingredients for the ultimate 12/13/14 sequential date story.
Of course, if one writes dates the European way, the last sequential day using consecutive integers passed last year on 11 December 2013.

Follow over the jump for sequential days using numbers other than consecutive integers.

Victoria Jaggard of Smithsonian Magazine answers her own question in After 12/13/14, What Are the Next Fun Dates for Math Lovers?
[N]umberphiles need not despair. Counting from one to 365 is just the simplest form of a mathematical tool called an integer sequence, says Neil J. A. Sloane, a visiting scientist at Rutgers University and founder of the Online Encyclopedia of Integer Sequences, or OEIS. "Our days are numbered," Sloane quips. So what other types of sequences can we look forward to celebrating this century?

Primes (11/13/17) and Mersenne Primes (07/13/17)[sic*]
Fibonacci Numbers (08/13/21)
Recamán's Sequence (07/13/20 and 08/25/43)
There's also an interesting sequence of a different sort next year, when Pi Day falls on 3/14/15--3.14.15.  The math instructors at the college where I teach are already planning something for the date.

*ETA: The next Mersenne Prime date should be 3/7/31, not 07/13/17.

No comments:

Post a Comment