51 may refer to:
*
51 (number)
51 (fifty-one) is the natural number following 50 and preceding 52.
In mathematics
Fifty-one is
* a pentagonal number as well as a centered pentagonal number and an 18-gonal number
*the 6th Motzkin number, telling the number of ways to dra ...
* The year
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51 BC
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Year 51 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Marcellus and Sulpicius (or, less frequently, year 703 ''Ab urbe condita''). The denomination 51 BC for this year has be ...
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AD 51
AD 51 ( LI) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Caesar and Scipio (or, less frequently, year 804 ''Ab urbe condita''). Th ...
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1951
Events
January
* January 4 – Korean War: Third Battle of Seoul – Chinese and North Korean forces capture Seoul for the second time (having lost the Second Battle of Seoul in September 1950).
* January 9 – The Government of the United ...
**
2051
In contemporary history, the third millennium of the anno Domini or Common Era in the Gregorian calendar is the current millennium spanning the years 2001 to 3000 (21st to 30th centuries). Ongoing futures studies seek to understand what is li ...
*
''51'' (film), a 2011 American horror film directed by Jason Connery
* "
Fifty-One
"Fifty-One" is the fourth episode of the fifth season of the American television crime drama series ''Breaking Bad'', and the 50th overall episode of the series. Written by Sam Catlin and directed by Rian Johnson, it originally aired on AMC in ...
", an episode of the American television drama series ''Breaking Bad''
*
''51'' (album), a 2012 mixtape by rapper Kool A.D.
* "Fifty One", a song by Karma to Burn from the album ''
V'', 2011
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