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Friday the 13th

Does every year contain at least one Friday the 13th?

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2011-09-12 23:12:22

Will Friday the 13th occur every year?

i decided i need a property for Fri the 13th to make my proof easier. i chose the fact that if Friday is the 13th, then Sunday is the 1st. From there, i set out to prove that every year, at least one Sunday will be the first of some month, thus proving the existence of Fri the 13th.

CLAIM: It doesn't matter what day the year starts on because no matter what day the year begins on, each day of the week is the first of some month (which would complete my proof). for this proof, i used modular arithmetic. its a lot more simple than it looks..

Let 0=Su, 1=M, 2=Tu, 3=W, 4=Th, 5=F, 6=Sa (so, I'm working in mod 7)

CASE 1: Non-Leap Year

Jan 1=0mod7

Feb 1=31=3mod7

Mar 1=31=3mod7

Apr 1=34=6mod7

May 1=36=1mod7

Jun 1=32=4mod7

Jul 1=34=6mod7

Aug 1=37=2mod7

Sep 1=33=5mod7

Oct 1=63=0mod7

Nov 1=31=3mod7

Dec 1=33=5mod7

This is the initial rotation of 1st's. Note that all of the numbers 0-6 (mod 7) are represented. This means that each day starts some month. CASE 2: Leap Year can also be studied based on CASE 1. Note that between Feb-Dec, which is what a Leap Year alters by one day, all of the numbers 0-6 are represented. Therefor, in a given year, Leap or Not, each day of the week falls on the first of some month, which implies that some month will always have a Friday the 13th. โ

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Related Questions

because of the way the months line up. There are 7 days in the week . It's given that the 13th will be on a Friday at least once

No. Every year has at least one Friday 13th, the most recent year with only one Friday 13th was 2011, with May 13th falling on Friday. The longest amount of time that can occur without a Friday 13th is fourteen months (1 year 2 months).

No month has a guaranteed Friday the 13th. Every year does though.

A Friday the 13th can occur in any month of a year. Every month will have one at some point or another. Each year there is at least one and at most three.

Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.Friday the 13th of May 2016.

well Friday the 13th is on Friday the 13th

It is impossible for Friday the 13th to occur in all 12 months of the one year.

Yes, there was. May 13 was a Friday, the only one that year. Every year will have at least one Friday the 13th, and having two is more common. In non-leap years, a February 13 Friday will be followed by a March 13 Friday and a November 13 Friday. In leap years, a February 13 Friday will be followed by an August 13 Friday.

When Friday is the 13th day in the month

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Friday the 13th part VI was made in 1986, and Friday the 13th part VII was made in 1988; but there was no Friday the 13th made in 1987.

Friday the 13th: Part 2 (1981)Friday the 13th: Part 3 (1982)Friday the 13th: The Final Chapter (aka Friday the 13th: Part 4) (1984)Friday the 13th: A New Beginning (aka Friday the 13th: Part 5) (1985)Jason Lives: Friday the 13th Part 6 (1986)Friday the 13th Part 7: The New Blood (1988)Friday the 13th Part 8: Jason Takes Manhattan (my personal favorite) (1989)Jason Goes to Hell: The Final Friday (aka Friday the 13th: Part 9) (1993)Jason X (aka Friday the 13th: Part 10) (2001)Freddy vs. Jason (aka Friday the 13: Part 11) (2003)Friday the 13th remake (aka Friday the 13th: Part 12) (2009)Friday the 13th: Part 2 remake (aka Friday the 13th: Part 13) (due to come out later in 2010)

1n 1987, a virus was detected that activated every Friday the 13th,affecting both .exe and.COM files and deleting any program you run on that day. It is called the Friday the 13th virus or Jerusalem.

Friday the 13th (1980) Friday the 13th Part 2 (1981) Friday the 13th Part III (1982) Friday the 13th: The Final Chapter (1984) Friday the 13th: A New Beginning (1985) Friday the 13th Part VI: Jason Lives (1986) Friday the 13th Part VII: The New Blood (1988) Friday the 13th Part VIII: Jason Takes Manhattan (1989) Jason Goes to Hell: The Final Friday (1993) Jason X (2002) Freddy vs. Jason (2003) Friday the 13th (remake) (2009)

Friday the 13th is up to at least 8

Friday the 13th (1980) Friday the 13th Part 2 (1981) Friday the 13th Part 3 (1982) Friday the 13th: The Final Chapter (1984) Friday the 13th: A New Beginning (1985) Friday the 13th Part VI: Jason Lives (1986) Friday the 13th Part VII: The New Blood (1988) Friday the 13th Part VIII: Jason Takes Manhattan (1989) Jason Goes to Hell: The Final Friday (1993) Jason X (2001) Freddy vs. Jason (2003) Friday the 13th (2009) Friday the 13th Part 2 (2017)

There are 12 Jason films;Friday The 13thFriday The 13th Part 2Friday The 13th Part 3Friday The 13th Part 4:The Final ChapterFriday The 13th Part 5:A New BeginningFriday The 13th Part 6:Jason LivesFriday The 13th Part 7:A New BloodFriday The 13th Part 8:Jason Takes ManhattanJason Goes To HellJason X Freddy Vs. JasonFriday The 13th: Remake

Paraskavedekatriaphobia- Fear of Friday the 13th.

To date, there have been twelve Friday the 13th movies: Friday the 13th (1980) Friday the 13th Part 2 (1981) Friday the 13th Part III (1982) Friday the 13th: The Final Chapter (1984) Friday the 13th: A New Beginning (1985) Friday the 13th Part VI: Jason Lives (1986) Friday the 13th Part VII: The New Blood (1988) Friday the 13th Part VIII: Jason Takes Manhattan (1989) Jason Goes to Hell: The Final Friday (1993) Jason X (2001) Freddy vs. Jason (2003) Friday the 13th (2009) - reboot The next Friday the 13th movie is due to be released sometime in 2015.

There were twelve Friday the 13th movies: Friday the 13th Friday the 13th Part II Friday the 13th Part III (originally in 3D) Friday the 13th: The Final Chapter Friday the 13th Part V: A New Beginning Friday the 13th Part VI: Jason Lives Friday the 13th Part VII: The New Blood Friday the 13th Part VIII: Jason Takes Manhattan Jason Goes To Hell: The Final Friday Jason X Freddy vs. Jason Friday the 13th (2009 remake) The final film was meant to be a remake of the first four. There was also a television show, Friday the 13th: The Series. All movies on TopRater: toprater.com/en/movies/objects/2300351-friday-the-13th-part-2-1981

Friday the 13th (1980) Friday the 13th Part 2 (1981) Friday the 13th Part III (1982) Friday the 13th: The Final Chapter (1984) Friday the 13th: A New Beginning (1985) Jason Lives: Friday the 13th Part VI (1986) Friday the 13th Part VII: The New Blood (1988) Friday the 13th Part VIII: Jason Takes Manhattan (1989) Jason Goes to Hell: The Final Friday (1993) Jason X (2001) Freddy vs. Jason (2003) Friday the 13th (2009)

Today is Friday the 13th, February 13th, 2009, that is!

The next Friday the 13th will be September 13, 2013. The last Friday the 13th happened in July 2012.

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