This Rare Friday the 13th

Juha-Matti Laurio writes to point out a Washington Times story about how special this particular Friday the 13th is. The digits in the numerical notation for the date add up to 13 — whether you write it in the US or the European form. From the article: "The phenomenon hasn't happened in 476 years, said Heinrich Hemme, a physicist at Germany's University of Aachen who crunched the numbers to find that the double-whammy last occurred Jan. 13, 1520."

Comments

European Dates

[RAMMS EIN]

``The digits in the numerical notation for the date add up to 13 whether you write it in the US or the European form.''

That may be related to the fact that they are the same digits, only in a different order.

By the way, there isn't really such a thing as a "European form". Different European countries have different conventions about writing dates.

Um.. not so phenomenal?

[Anonymous Coward]

Hasn't anyone noticed by now that this year, there was a Friday the 13th in January, which has the exact same digits as today? (01/13/2006 vs 10/13/2006)
Meaning.. this phenomenon has happened within the last year?

Re:Um.. not so phenomenal?

[suv4x4]

Hasn't anyone noticed by now that this year, there was a Friday the 13th in January, which has the exact same digits as today? (01/13/2006 vs 10/13/2006)
Meaning.. this phenomenon has happened within the last year?

Parent is right: 01/13/2006 was a Friday. You may wanna mod the dude up.

Not that it matters either way, but this omission further proves that fatalysts and numerologists are quite slow mentally.

Re:Um.. not so phenomenal?

[Samurai Cat!]

But it won't happen again until January 2024.

Ehhh! Wrong.

05/13/2011. :D

Re:Um.. not so phenomenal?

[telbij]

March 13, 2004 was a Saturday.

The first Friday the 13th..

[the_rajah]

On Friday, October 13, 1307 (a date possibly linked to the origin of the Friday the 13th legend), Philip had all French Templars simultaneously arrested, charged with numerous heresies, and tortured by French authorities nominally under the Inquisition until they allegedly confessed. This action released Philip from his obligation to repay huge loans from the Templars and justified his looting of Templar treasuries. From http://en.wikipedia.org/wiki/Knights_Templar

"Crunching" the numbers

[thisisjoel]

If anyone else wants to "crunch" those numbers, here's some Perl:

use Date::Calc qw( Add_Delta_Days Day_of_Week );

my $MAX_YEAR=3000;
my @date = (1,1,1);

sub summer { $a = 0; foreach (@_) { $a += $_ } $a }

while( $date[0] < $MAX_YEAR ) {
@date = Add_Delta_Days( @date, 1 );
if( $date[2] == 13
&& Day_of_Week( @date ) == 5
&& summer( split '', sprintf( "%04d-%02d-%02d", @date ) ) == 13
) {
printf( "%04d-%02d-%02d\n", @date );
}
}

I get 2006-01-13 as the most recent occurrence.

Re:I Just Knew I Shoulda Stayed In Bed Today

[Iron Condor]

Vaguely more interesting and almost veering ON topic for slashdot, in binary notation todays date would be

1010 1101 11111010110

...which just so happens to have thirteen "1"s in it.

Re:I Just Knew I Shoulda Stayed In Bed Today

[AstrumPreliator]

And the hex representation is...

A D 7D6

If you read it like "ADD 7 6" you get 13. I'd look for more examples but I just don't really care. If you're looking for something you will find it everywhere, regardless of what you're looking for.

That is of course unless it's your keys and you're late for work. ad7d6