# 42 (number)

﻿
42 (number)
42
Cardinal forty-two
Ordinal 42nd
(forty-second)
Factorization 2 · 3 · 7
Divisors 1, 2, 3, 6, 7, 14, 21, 42
Roman numeral XLII
Unicode symbol(s) *
Greek Prefix μβ
Binary 1010102
Octal 528
Duodecimal 3612

42 (forty-two) is the natural number immediately following 41 and directly preceding 43. The number has received considerable attention in popular culture as a result of its central appearance in The Hitchhiker's Guide to the Galaxy as the "Answer to the Ultimate Question of Life, the Universe, and Everything".

## Mathematics

The 3 × 3 × 3 magic cube with rows summing to 42.
• Given 27 same-size cubes whose nominal values progress from 1 to 27, a 3×3×3 magic cube can be constructed such that every row, column, and corridor, and every diagonal passing through the center, comprises 3 cubes whose sum of values is 42.
• Forty-two is a pronic number and an abundant number; its prime factorization 2 · 3 · 7 makes it the second sphenic number and also the second of the form { 2 · 3 · r }. As with all sphenic numbers of this form, the aliquot sum is abundant by 12. 42 is also the second sphenic number to be bracketed by twin primes; 30 is also a pronic number and also rests between two primes. 42 has a 14 member aliquot sequence 42, 54, 66, 78, 90, 144, 259, 45, 33, 15, 9, 4, 3, 1, 0 and is itself part of the aliquot sequence commencing with the first sphenic number 30. Further, 42 is the 10th member of the 3-aliquot tree.
• 42 is the product of the first three terms of Sylvester's sequence; like the first five such numbers it is also a primary pseudoperfect number.
• It is a Catalan number. Consequently; 42 is the number of noncrossing partitions of a set of five elements, the number of triangulations of a heptagon, the number of rooted ordered binary trees with six leaves, the number of ways in which five pairs of nested parentheses can be arranged, etc.
• It is the reciprocal of the sixth Bernoulli number.
• It is conjectured to be the scaling factor in the leading order term of the "sixth moment of the Riemann zeta function". In particular, Conrey & Ghosh have conjectured
${1 \over T}\int_0^T \left| \zeta\left({1 \over 2} + it\right) \right|^6\,dt \sim {42 \over 9!}\prod_p \left\{1-{1\over p}\right\}^4 \left( 1 + {4 \over p} + {1 \over p^2} \right) \log^9 T,$
where the infinite product is over all prime numbers, p.[1][2]
• It is the third pentadecagonal number. It is a meandric number and an open meandric number.
• 42 is a Størmer number.
• 42 is a perfect score on the USA Math Olympiad (USAMO)[3] and International Mathematical Olympiad (IMO).[4]
• In base 10, this number is a Harshad number and a self number, while it is a repdigit in base 4 (as 222).

## Science

• The atomic number of molybdenum.
• The angle in degrees for which a rainbow appears or the critical angle.
• In 1966, mathematician Paul Cooper theorized that the fastest, most efficient way to travel across continents would be to bore a straight hollow tube directly through the Earth, connecting a set of antipodes, evacuate it (remove the air), and then just fall through.[5] The first half of the journey consists of free-fall acceleration, while the second half consists of an exactly equal deceleration. The time for such a journey works out to be 42 minutes. Remarkably, even if the tube does not pass through the exact center of the Earth, the time for a journey powered entirely by gravity always works out to be 42 minutes, as long as the tube remains friction-free, as while gravity's force would be lessened, so would the distance traveled at an equal rate.[6][7] (The same idea was proposed, without calculation, by Lewis Carroll in 1893 in Sylvie and Bruno Concluded.[8])

## Religion

• In Japanese culture, the number 42 is considered unlucky because the numerals when pronounced separately — "shi ni" (four two) — sound like the phrase, "unto death".[11]
• There are 42 principles of Ma'at, the Ancient Egyptian personification of physical and moral law, order, and truth. In the judgement scene described in the Egyptian and the Book of the Coming/Going Forth by Day (the Book of the Dead (which evolved from the Coffin Texts and the Pyramid Texts)), there are 42 gods and goddesses of Egypt, personifying the principles of Ma'at, who ask questions of the departed, while Thoth records the answers, and the deceased's heart is weighed against the feather of Truth (Ma'at). These 42 correspond to the 42 Nomes (Governmental Units) of Egypt. If the departed successfully answers all 42, s/he becomes an Osiris.
• 42 is the number with which God creates the Universe in Kabbalistic tradition. In Kabbalah, the most significant name is that of the En Sof (also known as "Ein Sof", "Infinite" or "Endless"), who is above the Sefirot (sometimes spelled "Sephirot").[12] The Forty-Two-Lettered Name contains four combined names which are spelled in Hebrew letters (spelled in letters = 42 letters), which is the name of Azilut (or "Atziluth" "Emanation"). While there are obvious links between the Forty-Two Lettered Name of the Babylonian Talmud (see further up this page) and the Kabbalah's Forty-Two Lettered Name, they are probably not identical because of the Kabbalah's emphasis on numbers. The Kabbalah also contains a Forty-Five Lettered Name and a Seventy-Two Lettered Name.
• The number 42 appears in various contexts in Christianity. There are 42 generations (names) in the Gospel of Matthew's version of the Genealogy of Jesus; it is prophesied that for 42 months the Beast will hold dominion over the Earth (Revelation 13:5); 42 men of Beth-azmaveth were counted in the census of men of Israel upon return from exile (Ezra 2:24); God sent bears to maul 42 of the teenage boys who mocked Elisha for his baldness (2 Kings 2:23), etc.
• In Judaism, the number (in the Babylonian Talmud, compiled 375 AD to 499 AD) of the "Forty-Two Lettered Name" ascribed to God. Rab (or Rabhs), a 3rd century source in the Talmud stated "The Forty-Two Lettered Name is entrusted only to him who is pious, meek, middle-aged, free from bad temper, sober, and not insistent on his rights". [Source: Talmud Kidduschin 71a, Translated by Rabbi Dr. I. Epstein]. Maimonides felt that the original Talmudic Forty-Two Lettered Name was perhaps composed of several combined divine names [Maimonides "Moreh"]. The apparently unpronouncable Tetragrammaton provides the backdrop from the Twelve-Lettered Name and the Forty-Two Lettered Name of the Talmud.[citation needed]
• In Western Hermetic sphere work 42 is the sum of the values of the 'true' spheres, 3,4,5,6,7,8 & 9 each of which represent one aspect of the body of God through which we observe the world. 1 and 2 are considered modalities of existence and 10 is the completion we see from our own sphere, 11. The sum of the squares of each of these numbers make 216, or 6 x 6 x 6, the number of the beast, which is also the number of the names of God the Jews had to say once a year in the holy of holies to assure blessings from on high. The 'beast' is the perfect sphere, represented in 3 dimensions by 3 bounding circles, each with 6 radii, hence 666 being the number of the beast and directly being linked to 216 and 42. This is the foundation of Western Hermetic sphere work and is echoed in Pythagoreanism.[citation needed]
• The Gutenberg Bible is also known as the "42-line Bible", as the book contained 42 lines per page.
• The Forty-Two Articles (1552), largely the work of Thomas Cranmer, were intended to summarise Anglican doctrine, as it now existed under the reign of Edward VI.

## Popular culture

### The Hitchhiker's Guide to the Galaxy

The number 42 is in the novel The Hitchhiker's Guide to the Galaxy by Douglas Adams. The Answer to the Ultimate Question of Life, the Universe, and Everything is calculated by an enormous supercomputer over a period of 7.5 million years to be 42. Unfortunately no one knows what the question is. Thus, to calculate the Ultimate Question, a special computer was created, the size of a small planet, to use organic components, called "Earth". According to the novel Mostly Harmless, 42 is the street address of Stavromula Beta. In 1994, Adams created the 42 Puzzle, a game based on the number 42.

The book 42: Douglas Adams' Amazingly Accurate Answer to Life, the Universe and Everything[13] examines Adams' choice of the number 42 and also contains a compendium of some instances of the number in science, popular culture and humour.

### Works of Lewis Carroll

Lewis Carroll[14] made repeated use of this number in his writings.[15]

Examples of Carroll's use of 42:

• Alice's Adventures in Wonderland has 42 illustrations.
• Rule Forty-two in Alice's Adventures in Wonderland ("All persons more than a mile high to leave the court").
• Rule 42 of the Code in the preface[16] to The Hunting of the Snark ("No one shall speak to the Man at the Helm").
• In "fit the first" of The Hunting of the Snark the Baker had "forty-two boxes, all carefully packed, With his name painted clearly on each."[17]
• The White Queen announces her age as "one hundred and one, five months and a day", which - if the best possible date is assumed for the action of Through the Looking-Glass - gives a total of 37,044 days. With the further (textually unconfirmed) assumption that both Queens were born on the same day their combined age becomes 74,088 days, which is 42 x 42 x 42. Some commentators have asserted that this is deliberate on Carroll's part.[18]

### 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.
• 42 is one of The Numbers - 4, 8, 15, 16, 23, and 42 - featured in Lost. It is also the number tied to the character "Kwon".
• A made for TV movie 42: Forty Two Up - an installment in a series of documentaries wherein the director revisits the same group of British-born individuals every 7 years.[19]
• "42" is an episode of Doctor Who, set in real time lasting approximately 42 minutes.
• In an episode of "Stargate Atlantis" it is revealed that Rodney Mckay's password is made up of the birth years of several notable minds throughout history, and ends with the number 42. The character John Sheppard reveals that the number is the ultimate answer to life, the universe and everything, to the confusion of his alien companion.
• In the episode "Human" from Stargate Universe, the key to a code appears to be the number 46. Upon seeing this, Daniel Jackson exclaims: "Well, it's not the ultimate answer to life, the universe and everything. That's forty two. Hitchhiker's Guide to the Galaxy."
• On the game show "Jeopardy!", "Watson" the IBM supercomputer, has 42 "threads" in its avatar.[20]
• In season 3, episode 19 of The Office, Oscar (Oscar Nunez) guesses that there are 42 jelly beans in Pam's (Jenna Fischer) jar.

### Video games

• 42 Entertainment is the company responsible for several alternate reality games, including I Love Bees, Year Zero, and Why So Serious.
• In Spore, reaching the center of the galaxy yields a powerful item known as the "Staff of Life" which has a limited 42 uses. It also grants the player an achievement titled "42".
• In Fable II, the last in a series of ancient artifacts the player can find says "Now just think of the number 42."
• In Valve Corporation's Left 4 Dead 2, 42 is the number of Moustachios that must be shot in the Dark Carnival campaign's Whack-a-Mole style mini-game in order to unlock the STACH WACKER achievement.
• In Destroy All Humans!, the player goes into a parody of Area 51 called Area 42.

### Sports

Jackie Robinson in his now-retired number 42 jersey.

## Other fields

• +42 is the historic Country calling code for the former country of Czechoslovakia
• There are 42 US gallons in a barrel of oil.
• Tower 42 is a skyscraper in the City of London, formerly known as the NatWest Tower.
• The name of a Texan trick-taking game played with dominoes (see 42 (dominoes)).
• The number of spots (or pips, circular patches or pits) on a pair of standard six-sided dice.
• In New York City, 42nd Street is a main and very popular two-way thoroughfare. Landmarks on it include the Chrysler Building, Grand Central Terminal, 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.
• Popular gadget magazine Stuff did not produce an issue numbered 42, in honor of The Hitchhiker's Guide to the Galaxy, instead, the 41st issue was followed by the 43rd.
• The designation within ISO/IEC JTC1/SC7 of its working group on Architecture was chosen to be "WG 42" because architecture is the answer to "Life, the Universe and Everything", skipping over designations 26 through 41.
• Using the encoding A=1, B=2, C=3, etc., the sum of the codes of the letters in the words "BIG BANG" is 42.

## References

1. ^ J. B. Conrey & A. Ghosh, "A conjecture for the sixth power moment of the Riemann zeta-function" International Mathematics Research Notices (1998)
2. ^ J. B. Conrey & S. M. Gonek, "High moments of the Riemann zeta-function" Duke Math J. 107 3 (2001): 577 – 604
3. ^ Alex Zhai ties for second-highest score in 2007 USA Mathematical Olympiad - By Andrew Lovdahl Gargoyle staff reporter Posted Monday, May 7, 2007, The OG, news & student awards - Online Gargoyle
4. ^ CBC News staff, "Canadian math champ's skills add up to a perfect score" CBC News July 20, 2004. "A 16-year-old Canadian was one of four students who achieved a perfect score at an international mathematics competition. Jacob Tsimerman of Toronto scored 42 out of 42, making him one of 45 individual gold medallists at the 45th International Mathematical Olympiad in Athens."
5. ^ Cooper, Paul W. (1966). "Through the Earth in Forty Minutes". American Journal of Physics 34 (1): 68–69. doi:10.1119/1.1972773.
6. ^ "To Everywhere in 42 Minutes". Time. February 11, 1966. Retrieved 2008-05-18.
7. ^ "Jumping into a 7,965 mile deep hole". Archived from the original on June 02, 2008. Retrieved 2008-05-18.
8. ^ Carroll, Lewis (29 December 1893). "Chapter 7". Sylvie and Bruno Concluded. 2. illustrated by Harry Furniss. United Kingdom: Macmillan and Co.. "Each railway is in a long tunnel, perfectly straight: so of cource the middle of it is nearer the centre of the globe than the two ends: so every train runs half-way down-hill, and that gives it force enough to run the other half up-hill."
9. ^ url=http://www.microsoft.com/germany/presseservice/images/pressemappen/20jahre-windows/Windows-3.1-Logo.jpg
10. ^ "Framework for practical hexagonal-image processing". Journal of Electronic Imaging 11 (104). 2002. doi:10.1117/1.1426078. Retrieved January 17, 2010 (abstract only).
11. ^ Niiya, Brian. Japanese American history: an A-to-Z reference from 1868 to the present. Facts on File, Inc., 1993, p. 352
12. ^ Primack, Joel; Nancy E. Abrams. "In A Beginning...Quantum Cosmology and Kabbalah" (PDF). Retrieved 2008-03-14.
13. ^ Gill, Peter. "42: Douglas Adams' Amazingly Accurate Answer to Life the Universe and Everything". Guardian. Retrieved 03/04/2011.
14. ^ Lewis Carroll and Douglas Adams
15. ^ The Mystery of Lewis Carroll, Jenny Woolf
16. ^ The Hunting of the Snark, by Lewis Carroll
17. ^ The Hunting of the Snark, by Lewis Carroll
18. ^ What Lewis Carroll Taught Us: Alice's creator knew all about role-playing. by Seth Lerer, March 4, 2010
19. ^ 42: Forty Two Up at IMDB
20. ^ http://www.slate.com/id/2284721/ Ken Jennings

Wikimedia Foundation. 2010.