Movatterモバイル変換


[0]ホーム

URL:


Jump to content
WikipediaThe Free Encyclopedia
Search

42 (number)

From Wikipedia, the free encyclopedia
For other uses, see42.
Natural number
← 4142 43 →
Cardinalforty-two
Ordinal42nd
(forty-second)
Factorization2 × 3 × 7
Divisors1, 2, 3, 6, 7, 14, 21, 42
Greek numeralΜΒ´
Roman numeralXLII,xlii
Binary1010102
Ternary11203
Senary1106
Octal528
Duodecimal3612
Hexadecimal2A16

42 (forty-two) is thenatural number following41 and preceding43.

Mathematics

[edit]

42 is apronic number,[1] anabundant number[2] as well as ahighly abundant number,[3] apractical number,[4] and aCatalan number.[5]

The 42-sidedtetracontadigon is the largest suchregular polygon that can only tile a vertex alongside other regular polygons, withouttiling the plane.[6][7][8]

42 is themagic constant of the smallest non-trivialmagic cube, a3×3×3{\displaystyle 3\times 3\times 3} cube with entries of 1 through 27, where every row, column, corridor, and diagonal passing through the center sums to forty-two.[9][10]

42 can be expressed as thesum of three cubes: (80,435,758,145,817,515)3 + (12,602,123,297,335,631)3 + (-80,538,738,812,075,974)3 .[11]

The 3×3×3simple magic cube with rows summing to 42

Wisdom literature, religion, and philosophy

[edit]
  • Abrahamic religions
    • InJudaism, by some traditions theTorah scroll is written with no fewer than 42 lines per column, based on the journeys of Israel.[12] In the present day, 42 lines is the most common standard,[13] but various traditions remain in use (seeSefer Torah).
    • 42 is the number with which God creates the Universe inKabbalistic 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").[14] 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 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. 42 letters make the Ana beKo'ach prayer.[15]

Popular culture

[edit]

The Hitchhiker's Guide to the Galaxy

[edit]
The Answer to the Ultimate Question of Life, The Universe, and Everything
Main article:Phrases from The Hitchhiker's Guide to the Galaxy § The Answer to the Ultimate Question of Life, the Universe, and Everything is 42

The number 42 is, inThe Hitchhiker's Guide to the Galaxy byDouglas Adams, the "Answer to the Ultimate Question of Life, the Universe, and Everything", calculated byan enormous supercomputer named Deep Thought over a period of 7.5 million years. Unfortunately, no one knows what the question is. Thus, to calculate the Ultimate Question, a special computer the size of a small planet was built from organic components and named "Earth". The Ultimate Question "What do you get when you multiply six by nine"[16] is found by Arthur Dent and Ford Prefect in the second book of the series,The Restaurant at the End of the Universe. This appeared first in theradio play and later in the novelization ofThe Hitchhiker's Guide to the Galaxy.

The fourth book in the series, the novelSo Long, and Thanks for All the Fish, contains 42 chapters.According to the novelMostly Harmless, 42 is the street address of Stavromula Beta.

In 1994, Adams created the42 Puzzle, a game based on the number 42. Adams says hepicked the number simply as a joke, with no deeper meaning.

Google also has a calculatoreaster egg when one searches "the answer to the ultimate question of life, the universe, and everything." Once typed (all in lowercase), the calculator answers with the number 42.[17]

Jackie Robinson

[edit]
Jackie Robinson in his now-retired number 42 jersey

Other

[edit]

In Japanese culture, the number 42 is considered unlucky because the numerals when pronounced separately—shi ni (four two)—sound like the word "dying",[18] like the Latin word "mori".

References

[edit]
  1. ^Sloane, N. J. A. (ed.)."Sequence A002378 (Oblong (or promic, pronic, or heteromecic) numbers)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2016-05-30.
  2. ^Sloane, N. J. A. (ed.)."Sequence A005101 (Abundant numbers (sum of divisors of m exceeds 2m).)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2024-01-07.
  3. ^Sloane, N. J. A. (ed.)."Sequence A002093 (Highly abundant numbers)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2024-11-14.
  4. ^Sloane, N. J. A. (ed.)."Sequence A005153 (Practical numbers)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2024-11-14.
  5. ^Sloane, N. J. A. (ed.)."Sequence A000108 (Catalan numbers)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2016-05-30.
  6. ^Grünbaum, Branko;Shepard, Geoffrey (November 1977)."Tilings by Regular Polygons"(PDF).Mathematics Magazine.50 (5). Taylor & Francis, Ltd.:229–230.doi:10.2307/2689529.ISSN 0025-570X.JSTOR 2689529.S2CID 123776612.Zbl 0385.51006.
  7. ^Dallas, Elmslie William (1855)."Part II. (VII): Of the Circle, with its Inscribed and Circumscribed Figures − Equal Division and the Construction of Polygons".The Elements of Plane Practical Geometry. London: John W. Parker & Son, West Strand. p. 134.
  8. ^Jardine, Kevin."Shield - a 3.7.42 tiling".Imperfect Congruence. Retrieved2023-01-09. 3.7.42 as a unit facet in an irregular tiling.
  9. ^Andrews, William Symes (1960).Magic Squares and Cubes(PDF) (2nd ed.). New York:Dover Publications. p. 65.doi:10.2307/3603128.ISBN 9780486206585.JSTOR 3603128.MR 0114763.OCLC 1136401.S2CID 121770908.Zbl 1003.05500.{{cite book}}:ISBN / Date incompatibility (help)
  10. ^Sloane, N. J. A. (ed.)."Sequence A027441 (a(n) equal to (n^4 + n)/2 (Row sums of an n X n X n magic cube, when it exists).)".TheOn-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved2024-01-07.
  11. ^Booker, Andrew R.; Sutherland, Andrew V. (2021)."On a question of Mordell".Proceedings of the National Academy of Sciences.118 (11).arXiv:2007.01209.Bibcode:2021PNAS..11822377B.doi:10.1073/pnas.2022377118.PMC 7980389.PMID 33692126.
  12. ^Ganzfried, R. Solomon (1902).קסת הסופר [Keset haSofer] (in Hebrew and English). Translated by Friendman, Jen (First ed.). Bardejov: דפוס יוסף מאיר בלייער.It is the custom to have no fewer than 48 lines, representing the journeys of Israel, and some say no fewer than 42, because of what God did in the Sinai wilderness at Kadesh. Also, we don't have more than 60 lines, representing the 60 myriads of Israel who received the Torah.
  13. ^Jacobs, Joseph; Eisenstein, Judah; Executive Committee of the Editorial Board; Blau, Ludwig (1906)."Scroll of the Law (Hebrew, "Sefer Torah")".Jewish Encyclopedia. Retrieved12 February 2020.(At the present day the forty-two-lined column is the generally accepted style of the scroll, its length being about 24 inches.)
  14. ^Joel Primack; Nancy E. Abrams."In A Beginning...Quantum Cosmology and Kabbalah"(PDF). Retrieved2008-03-14.
  15. ^"The Prayer of the Kabbalist". Archived fromthe original on 2025-09-18. Retrieved2025-10-10.
  16. ^"Mathematical Fiction: Hitchhiker's Guide to the Galaxy (1979)". Retrieved30 November 2016. See this website for possible explanations of this seeming error.
  17. ^"17 amazing Google Easter eggs".CBS News. November 11, 2011. RetrievedNovember 1, 2022.
  18. ^Niiya, Brian. Japanese American history: an A-to-Z reference from 1868 to the present. Facts on File, Inc., 1993, p. 352

External links

[edit]
Wikiquote has quotations related to42 (number).
Look upforty-two in Wiktionary, the free dictionary.

Media related to42 (number) at Wikimedia Commons

0 to 199
200 to 399
400 to 999
1000s and 10,000s
1000s
10,000s
100,000s to 10,000,000,000,000s
Retrieved from "https://en.wikipedia.org/w/index.php?title=42_(number)&oldid=1323351727"
Categories:
Hidden categories:

[8]ページ先頭

©2009-2025 Movatter.jp