42 (number)

42 (forty-two) is the natural number following 41 and preceding 43.

Template:Numbers 40s
Cardinal	42 forty-two
Ordinal	42nd forty-second
Factorization	2 × 3 × 7
Divisors	2, 3, 6, 7, 14, 21
Roman numeral	XLII
Binary	101010
Hexadecimal	2A
IEEE Float	42.0 = 42280000 hexadecimal
Hebrew	מב (Mem Bet)

In mathematics

Bracketed by twin primes, this composite number's factorization makes it a sphenic number, as it is the product of the first three terms of Sylvester's sequence.

It is also

the third 15-gonal number;
a Catalan number;
the reciprocal of a Bernoulli number;
a meandric number and an open meandric number;
a square-free integer;
the sum of the totient function for the first eleven integers.
in base 10, a Harshad number and a self number;
a repdigit in base 4 (222);
a perfect score on the USA Math Olympiad (USAMO) and International Mathematical Olympiad (IMO).

42 is conjectured to be the "third moment of the Riemann zeta function". That means that when

{1 \over T}\int _{0}^{T}\left|\zeta \left({1 \over 2}+it\right)\right|^{6}\,dt

is expanded as in powers of log(T), the leading coefficient—that of the 9th-degree term—is 42.

In science

The atomic number of molybdenum. The element following molybdenum with atomic number 43 (technetium) has no stable isotopes.
The number of teeth wolves and dogs (canines) have.
42° is the critical angle of refraction by water - it is the angle between a rainbow and the antisolar point. See The Rainbow Bridge (Sample Chapter)
The light leaving a rainbow is spread over a wide angle, with a maximum intensity around 42°

Astronomy

Messier object M42, a magnitude 5.0 diffuse nebula in the constellation Orion, also known as the Orion Nebula
The New General Catalogue object NGC 42, a spiral galaxy in the constellation Pegasus
The Saros number of the solar eclipse series which began on 1577 BC April 28 and ended on 297 BC June 5. The duration of Saros series 42 was 1280.1 years, and it contained 72 solar eclipses.
The Saros number of the lunar eclipse series which began on 1293 BC January 24 and ended on 59 April 15. The duration of Saros series 42 was 1352.2 years, and it contained 76 lunar eclipses.
Gliese 42 is a magnitude 7.17 K3 V orange dwarf nearby star (14.5 pc) in Sculptor, also known as HD 5133, CD-31°325, G269-049, GCTP 177.00, and LHS 1163.
Ross 42 is a magnitude 11.52 dM4 e red dwarf nearby star (14.1 pc) in Orion, also known as Gliese 206, G097-047, and GCTP 1259.00.
The planet Uranus' north and south poles face the sun 42 years before switching, (example) the north pole experiences 42 years of summer and 42 years of winter and vice versa.

In religion

The number of generations in the Gospel of Matthew's version of the Genealogy of Jesus
The number of months the Beast will hold dominion over the Earth (Revelation 13:5)
In the ancient Chinese text the Tao Te Ching by Lao Tsu, chapter 42 is an explanation of the universe
The number of men of Beth-azmaveth in the census of men of Israel upon return from exile (Ezra 2:24)
God sends bears to maul 42 of the youths who mock Elisha for his baldness (2 Kings 2:23)
There are 42 principles of Ma'at
The number of lines on each page of the Gutenberg Bible, the oldest surviving book printed with movable type

In pop culture

The Ultimate Answer

The number 42 is The Answer to Life, the Universe, and Everything, according to Douglas Adams' series The Hitchhiker's Guide to the Galaxy. Numerous others have parodied this supposed mysticism of 42.
- If one types "the answer to life, the universe, and everything" into Google, one will receive the answer 42 by Google calculator (See the above).
- Geoff Fortytwo (formerly Busker) is a computer scientist who legally changed his surname in 1997 to reflect the Answer.
- Using a word processor known as an AlphaSmart, when one types in an equation whose solution is 42, the sentence "The answer to life, the universe and everything" appears before displaying 42.
- In one of the subsequent books in the The Hitchhiker's Guide to the Galaxy series, it is implied that the question to which 42 is the answer is "What do you get when you multiply six by nine?". It has been noted that six times nine equals 42 in base 13. Whilst some have been tempted to infer significance in this (for example, that God has thirteen fingers), Douglas Adams denied that he was aware of this alternate solution when he wrote the book. He stated, "I may be a pretty sad person, but I don't make jokes in base 13."
In the Strong Bad e-mail cartoons on the Homestar Runner website, Strong Bad's Lappy 486 laptop computer weighs 42 pounds
The number of student "players" in a regulation Battle Royale
In the U.S. cartoon Foster's Home For Imaginary Friends, Bloo declares that 2 + 3 = 42.
In the game of Risk, there are 42 territories to be conquered
In the movie Mission: Impossible II the 42nd level is where a deadly virus is contained.
In the T.V. series "Lost", the last of the mysterious numbers is 42.

In music

The movement number of the Hallelujah Chorus in Handel's Messiah
The Level 42 band
The Disco Biscuits band from Philadelphia has a song titled "42"
In the song "Fat" by Weird Al, Yankovic states that his shadow weighs 42 pounds. In his new song "You're Pitiful," he sings about a 42 year-old nerd
The Rolling Stones' song "Undercover of the Night" makes reference to a "Center 42"

In television and film

The Kumars at No. 42 television series. In 2003, Sanjeev Bhaskar hosted a BBC show nominating The Hitchhiker's Guide to the Galaxy as Britain's Best Loved Book. During the show Bhaskar stated that the Kumars' house number was in honour of the book
Appears as the number of hits on the hit counter at the bottom of a fake website for the show Arrested Development on FOX
In the movie Finding Nemo, Nemo is taken to Dr. Philip Sherman's office at 42 Wallaby Way, Sydney NSW
In the movie 28 Days Later, a radio transmission that promises an answer to the infection leads the protagonists to roadblock 42
In the movie Teen Wolf, the number on Michael J. Fox's basketball jersey is 42
In The X-Files, Mulder has seen Plan 9 from Outer Space 42 times, his apartment number is 42.
42 is one of "The Numbers" on the television show Lost, along with 4, 8, 15, 16 and 23.
42 is the final coordinate of the ___location of the legendary Cutthroat Island.
In the Family Guy episode "The Thin White Line," when Brian goes into rehab his room number is 42. Also when asked Peter's Age, Stewie instantly answers 42
In the opening sequence of every show of Futurama, on the left side a sign says 42.
Matthew Broderick's character, Steven Kovacs, in the movie The Cable Guy has this apartment number.
The number of the spoofed government film in the Monty Python sketch "How Not To Be Seen" from episode 24. (Douglas Adams also appeared as a doctor in episode 42)
The number present on the jersey of a lion on the PBS show "Between the Lions" (in memory of Douglas Adams)
In AdventureQuest, there is a door with the number 42 on it, which, if you click on it, it says "This door contains the answer to Life, the Universe, and Everything..." a reference to The Hitchhiker's Guide to the Galaxy
Hugh Laurie's character, Gregory House, of the television show House claimed 42 was his lucky number in the episode "All In."
Summer of '42, a "coming-of-age" movie (1971) and novelisation written by Herman Raucher
In Mission Impossible 2, the floor number in the BioCyte building in Sydney, Australia, where the deadly virus "Chimera" is stored and manufactured is 42
On Neopets a programmer named Ollie constantly says 42 in reply to Neomails about the Altador Plot
On the television program Star Trek: The Next Generation, the Starship Enterprise (NCC-1701-D) has 42 decks.
42 and 47 are cult figure integers, and tongue-in-cheek legends concerning these numbers are numerous.

In video games

Clubhouse Games, 42 All-Time Classics in Europe, is a video game for the Nintendo DS, recently announced on May 9, 2006 at E3.
A level in the game Destroy All Humans! is named "Area 42", an obvious spoof on Area 51

In sports

The number of laws of cricket.

Jackie Robinson in his now-retired number 42 jersey.

The jersey number of Jackie Robinson, which is the first and only number retired by all Major League Baseball teams
The jersey number of football Hall of Famer, Ronnie Lott, safety for the San Francisco 49ers who retired his jersey number in 2003.
The jersey number of Pat Tillman, which was retired on November 13, 2004 by Arizona State University
The jersey number of Mariano Rivera, New York Yankees closer (the last player to wear Robinson's number, under a grandfather clause)
The approximate length of a Marathon race in kilometers

In technology

42 is a common metasyntactic variable used by programmers. In the TIFF image file format, the second 16-bit word of every file is 42, which is used together with the first word to indicate byte order. In the reiser4 file system, 42 is the inode number of the root directory.

The code number for the Microsoft .NET platform is 42, since it is their answer to "The Answer to Life, the Universe, and Everything". It also happens to be the building number that the Microsoft .NET CLR is built in.

The help entry 42 (accessed by typing ":h 42" in command mode) in the Vim text editor displays a reference to Douglas Adams.

In other fields

The number of U.S. gallons of oil contained in one barrel of oil
The age at which Elvis Presley died
The maximum number received of any one present in the song The Twelve Days of Christmas
In Lewis Carroll's book, The Hunting of the Snark, which he wrote at the age of 42, "one who was famed for the number of things/ He forgot when he entered the ship:" had "...forty-two boxes, all carefully packed,/ With his name painted clearly on each:/ But, since he omitted to mention the fact/ They were all left behind on the beach." Its preface also references a 'rule 42' ("No one shall speak to the Man at the Helm")
Carroll's Alice has 42 illustrations. In Chapter XII, the king explains "the oldest rule in the book": "Rule Forty-two. All persons more than a mile high to leave the court"
The sum of the numbers or pips on a pair of conventional (six-sided) dice
The name of a Texan trick-taking game played with dominoes (see 42 (dominoes)).
The number of the French department Loire.
The name of an equipment finance and lease management product built by Northern Arch
The minimum age one had to have been to be elected a consul in the Roman Republic

Part of the name of 42 BELOW, a vodka produced in New Zealand.
The number of perfect squares formed by the grid at a 19x19 Go board, when the "squares" are slightly rectangular with the ratio 13/12, as required by tradition.
The number of hours that the potion caused Juliet to sleep for (Shakespeare, Romeo and Juliet, Act IV, Scene 1, line 105)
In Japanese, 4 (shi) and 2 (ni) are together pronounced like "going to death" (死に). Because of that, in Japan, 42 is considered as a disastrous number
Age (in years) of the horse that drove Mr. Pickwick to Golden Cross, as reported by a cabman (The Pickwick Papers, Chapter III)
The number of holes on a Connect Four game board
The number of stones each side has in the most common game type of Mancala with two rows of six pits with seven pieces in each pit
The number of legs on the Centipede in Roald Dahl's book James and the Giant Peach
The world record for the most amount of people in one car is 42
In Scene One of "The Island" by Athol Fugard, John remarks that, "[Cell block] Number 42 is practising the Zulu War Dance"
There were originally 42 columns and 42 figures from Greek myth in the Parthenon
The number of different whiskies used to blend J&B
The number of enemies Gimli the Dwarf kills at the Battle of the Hornburg in The Lord of the Rings (changed to 43 in the film version)
Bill Clinton was the 42nd President of the United States
Washington became the 42nd state in the Union on November 11, 1889
In New York City, 42nd Street is a main and very popular two-way thoroughfare. Landmarks on it include the Chrysler Building, Grand Central Station, the main branch of the New York Public Library, and Times Square. The New York City street is also the setting for a movie by the same name (which also gave fame to its eponymous title song), and which later inspired a musical adaptation, 42nd Street
In Oscar Wilde's book The Importance of Being Earnest, 42 is the age that Gwendolen Fairfax wishes Cecily Cardew were.
The number of teeth in Moby Dick.
The age at which the mathematician Alexander Grothendieck retired.

Historical years

42 A.D., 42 B.C., 1942, 2042, etc.

External links

Deep Thought (another list of the meanings of the number 42, with a heavy Hitchhiker's Guide to the Galaxy slant)
7Seekers The name of the Book/CD/DVD set on this website is 42 Reasons
42 A website dedicated wholly to the number 42