23 (number)

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22 23 24
Cardinal twenty-three
Ordinal 23rd
(twenty-third)
Numeral system trivigesimal
Factorization prime
Prime 9th
Divisors 1, 23
Greek numeral ΚΓ´
Roman numeral XXIII
Binary 101112
Ternary 2123
Senary 356
Octal 278
Duodecimal 1B12
Hexadecimal 1716

23 (twenty-three) is the natural number following 22 and preceding 24.

Contents

In mathematics

Twenty-three is the ninth prime number, the smallest odd prime that is not a twin prime. [1] It is, however, a cousin prime with 19, and a sexy prime with 17 and 29; while also being the largest member of the first prime sextuplet (7, 11, 13, 17, 19, 23). [2] Twenty-three is also the fifth factorial prime, [3] the second Woodall prime, [4] and a happy number in decimal. [5] It is an Eisenstein prime with no imaginary part and real part of the form It is also the fifth Sophie Germain prime [6] and the fourth safe prime, [7] and the next to last member of the first Cunningham chain of the first kind to have five terms (2, 5, 11, 23, 47). [8] Since 14! + 1 is a multiple of 23, but 23 is not one more than a multiple of 14, 23 is the first Pillai prime. [9] 23 is the smallest odd prime to be a highly cototient number, as the solution to for the integers 95, 119, 143, and 529. [10]

Otherwise, is the largest even number that is not the sum of two abundant numbers.
A related coincidence is that 365 times the natural logarithm of 2, approximately 252.999, is very close to the number of pairs of 23 items and 22nd triangular number, 253.

Hilbert's problems are twenty-three problems in mathematics published by German mathematician David Hilbert in 1900.

Mersenne numbers

The first Mersenne number of the form that does not yield a prime number when inputting a prime exponent is with [30]

On the other hand, the second composite Mersenne number contains an exponent of twenty-three:

The twenty-third prime number (83) is an exponent to the fourteenth composite Mersenne number, which factorizes into two prime numbers, the largest of which is twenty-three digits long when written in base ten: [31] [32]

Further down in this sequence, the seventeenth and eighteenth composite Mersenne numbers have two prime factors each as well, where the largest of these are respectively twenty-two and twenty-four digits long,

Where prime exponents for and add to 106, which lies in between prime exponents of and , the index of the latter two (17 and 18) in the sequence of Mersenne numbers sum to 35, which is the twenty-third composite number. [33]

is twenty-three digits long in decimal, and there are only three other numbers whose factorials generate numbers that are digits long in base ten: 1, 22, and  24.

In geometry

The Leech lattice Λ24 is a 24-dimensional lattice through which 23 other positive definite even unimodular Niemeier lattices of rank 24 are built, and vice-versa. Λ24 represents the solution to the kissing number in 24 dimensions as the precise lattice structure for the maximum number of spheres that can fill 24-dimensional space without overlapping, equal to 196,560 spheres. These 23 Niemeier lattices are located at deep holes of radii 2 in lattice points around its automorphism group, Conway group . The Leech lattice can be constructed in various ways, which include:

Conway and Sloane provided constructions of the Leech lattice from all other 23 Niemeier lattices. [34]

Twenty-three four-dimensional crystal families exist within the classification of space groups. These are accompanied by six enantiomorphic forms, maximizing the total count to twenty-nine crystal families. [35] Five cubes can be arranged to form twenty-three free pentacubes, or twenty-nine distinct one-sided pentacubes (with reflections). [36] [37]

There are 23 three-dimensional uniform polyhedra that are cell facets inside uniform 4-polytopes that are not part of infinite families of antiprismatic prisms and duoprisms: the five Platonic solids, the thirteen Archimedean solids, and five semiregular prisms (the triangular, pentagonal, hexagonal, octagonal, and decagonal prisms).

23 Coxeter groups of paracompact hyperbolic honeycombs in the third dimension generate 151 unique Wythoffian constructions of paracompact honeycombs. 23 four-dimensional Euclidean honeycombs are generated from the cubic group, and 23 five-dimensional uniform polytopes are generated from the demihypercubic group.

In two-dimensional geometry, the regular 23-sided icositrigon is the first regular polygon that is not constructible with a compass and straight edge or with the aide of an angle trisector (since it is neither a Fermat prime nor a Pierpont prime), nor by neusis or a double-notched straight edge. [38] It is also not constructible with origami, however it is through other traditional methods for all regular polygons. [39]

In science and technology

In religion

Music

Film and television

Other fields

In sports

Related Research Articles

2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures.

10 (ten) is the even natural number following 9 and preceding 11. Ten is the base of the decimal numeral system, the most common system of denoting numbers in both spoken and written language.

11 (eleven) is the natural number following 10 and preceding 12. It is the first repdigit. In English, it is the smallest positive integer whose name has three syllables.

19 (nineteen) is the natural number following 18 and preceding 20. It is a prime number.

21 (twenty-one) is the natural number following 20 and preceding 22.

22 (twenty-two) is the natural number following 21 and preceding 23.

25 (twenty-five) is the natural number following 24 and preceding 26.

72 (seventy-two) is the natural number following 71 and preceding 73. It is half a gross or 6 dozen.

84 (eighty-four) is the natural number following 83 and preceding 85.

32 (thirty-two) is the natural number following 31 and preceding 33.

31 (thirty-one) is the natural number following 30 and preceding 32. It is a prime number.

61 (sixty-one) is the natural number following 60 and preceding 62.

63 (sixty-three) is the natural number following 62 and preceding 64.

104 is the natural number following 103 and preceding 105.

1000 or one thousand is the natural number following 999 and preceding 1001. In most English-speaking countries, it can be written with or without a comma or sometimes a period separating the thousands digit: 1,000.

127 is the natural number following 126 and preceding 128. It is also a prime number.

144 is the natural number following 143 and preceding 145.

271 is the natural number after 270 and before 272.

5 (five) is a number, numeral and digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. It has garnered attention throughout history in part because distal extremities in humans typically contain five digits.

744 is the natural number following 743 and preceding 745.

References

  1. Sloane, N. J. A. (ed.). "SequenceA007510(Single (or isolated or non-twin) primes: Primes p such that neither p-2 nor p+2 is prime.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 5 December 2022.
  2. Sloane, N. J. A. (ed.). "SequenceA001223(Prime gaps: differences between consecutive primes.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 11 June 2023.
  3. Sloane, N. J. A. (ed.). "SequenceA088054(Factorial primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  4. Sloane, N. J. A. (ed.). "SequenceA050918(Woodall primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  5. Sloane, N. J. A. (ed.). "SequenceA007770(Happy numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  6. Sloane, N. J. A. (ed.). "SequenceA005384(Sophie Germain primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  7. Sloane, N. J. A. (ed.). "SequenceA005385(Safe primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  8. Sloane, N. J. A. (ed.). "SequenceA192580(Monotonic ordering of set S generated by these rules: if x and y are in S and xy+1 is a prime, then xy+1 is in S, and 2 is in S.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 11 June 2023.
    "2, 5, 11, 23, 47 is the complete Cunningham chain that begins with 2. Each term except the last is a Sophie Germain prime A005384."
  9. Sloane, N. J. A. (ed.). "SequenceA063980(Pillai primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  10. Sloane, N. J. A. (ed.). "SequenceA100827(Highly cototient numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  11. Sloane, N. J. A. (ed.). "SequenceA069151(Concatenations of consecutive primes, starting with 2, that are also prime)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  12. (sequence A045345 in the OEIS )
  13. "Puzzle 31.- The Average Prime number, APN(k) = S(Pk)/k". www.primepuzzles.net. Retrieved 29 November 2022.
  14. Sloane, N. J. A. (ed.). "SequenceA005235(Fortunate numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  15. Sloane, N. J. A. (ed.). "SequenceA002182(Highly composite numbers, definition (1): numbers n where d(n), the number of divisors of n (A000005), increases to a record.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 9 October 2023.
  16. Sloane, N. J. A. (ed.). "SequenceA048242(Numbers that are not the sum of two abundant numbers (not necessarily distinct).)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 9 October 2023.
  17. "Sloane's A000055: Number of trees with n unlabeled nodes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Archived from the original on 29 November 2010. Retrieved 19 December 2021.
  18. Sloane, N. J. A. (ed.). "SequenceA001190(Wedderburn-Etherington numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  19. Chamberland, Marc. "Binary BBP-Formulae for Logarithms and Generalized Gaussian-Mersenne Primes" (PDF).
  20. Weisstein, Eric W. "Cyclotomic Integer". mathworld.wolfram.com. Retrieved 15 January 2019.
  21. Sloane, N. J. A. (ed.). "SequenceA228611(Primes p such that the largest consecutive pair of -smooth integers is the same as the largest consecutive pair of -smooth integers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 31 May 2016.
  22. Weisstein, Eric W. "Birthday Problem". mathworld.wolfram.com. Retrieved 19 August 2020.
  23. Sloane, N. J. A. (ed.). "SequenceA038133(From a subtractive Goldbach conjecture: odd primes that are not cluster primes.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 26 December 2022.
  24. Sloane, N. J. A. (ed.). "SequenceA006203(Discriminants of imaginary quadratic fields with class number 3 (negated).)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 20 March 2024.
  25. Sloane, N. J. A. (ed.). "SequenceA023679(Discriminants of complex cubic fields (negated).)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 20 March 2024.
  26. Guy, Richard; Unsolved Problems in Number Theory, p. 7 ISBN   1475717385
  27. Sloane, N. J. A. (ed.). "SequenceA003459(Absolute primes (or permutable primes): every permutation of the digits is a prime.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 10 January 2024.
  28. Sloane, N. J. A. (ed.). "SequenceA004022(Primes of the form (10^k - 1)/9. Also called repunit primes or repdigit primes.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 10 January 2024.
  29. Sloane, N. J. A. (ed.). "SequenceA004023(Indices of prime repunits: numbers n such that 11...111 (with n 1's) equal to (10^n - 1)/9 is prime.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 10 January 2024.
  30. Sloane, N. J. A. (ed.). "SequenceA000225(Mersenne numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 16 February 2023.
  31. Sloane, N. J. A. (ed.). "SequenceA136030(Smallest prime factor of composite Mersenne numbers.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 12 June 2023.
  32. Sloane, N. J. A. (ed.). "SequenceA136031(Largest prime factor of composite Mersenne numbers.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 12 June 2023.
  33. Sloane, N. J. A. (ed.). "SequenceA002808(The composite numbers: numbers n of the form x*y for x > 1 and y > 1.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 9 January 2024.
  34. Conway, John Horton; Sloane, N. J. A. (1982). "Twenty-three constructions for the Leech lattice". Proceedings of the Royal Society A . 381 (1781): 275–283. Bibcode:1982RSPSA.381..275C. doi:10.1098/rspa.1982.0071. ISSN   0080-4630. MR   0661720. S2CID   202575295.
  35. Sloane, N. J. A. (ed.). "SequenceA004032(Number of n-dimensional crystal families.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 21 November 2022.
  36. Sloane, N. J. A. (ed.). "SequenceA000162(Number of three dimensional polyominoes (or polycubes) with n cells.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 6 January 2023.
  37. Sloane, N. J. A. (ed.). "SequenceA038119(Number of n-celled solid polyominoes (or free polycubes, allowing mirror-image identification))". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  38. Arthur Baragar (2002) Constructions Using a Compass and Twice-Notched Straightedge, The American Mathematical Monthly, 109:2, 151-164, doi : 10.1080/00029890.2002.11919848
  39. P. Milici, R. Dawson The equiangular compass December 1st, 2012, The Mathematical Intelligencer, Vol. 34, Issue 4 https://www.researchgate.net/profile/Pietro_Milici2/publication/257393577_The_Equiangular_Compass/links/5d4c687da6fdcc370a8725e0/The-Equiangular-Compass.pdf
  40. H. Wramsby, K. Fredga, P. Liedholm, "Chromosome analysis of human oocytes recovered from preovulatory follicles in stimulated cycles" New England Journal of Medicine316 3 (1987): 121 – 124
  41. Barbara J. Trask, "Human genetics and disease: Human cytogenetics: 46 chromosomes, 46 years and counting" Nature Reviews Genetics3 (2002): 769. "Human cytogenetics was born in 1956 with the fundamental, but empowering, discovery that normal human cells contain 46 chromosomes."
  42. Newell, David B.; Tiesinga, Eite (2019). The International System of Units (SI). NIST Special Publication 330. Gaithersburg, Maryland: National Institute of Standards and Technology. doi:10.6028/nist.sp.330-2019. S2CID   242934226.
  43. RFC   854, Telnet Protocol Specification
  44. ""The Lord is My Shepherd, I Shall Not Want" – Meaning of Psalm 23 Explained". Christianity.com. Retrieved 7 June 2021.
  45. Miriam Dunson, A Very Present Help: Psalm Studies for Older Adults. New York: Geneva Press (1999): 91. "Psalm 23 is perhaps the most familiar, the most loved, the most memorized, and the most quoted of all the psalms."
  46. Living Religions: An Encyclopaedia of the World's Faiths, Mary Pat Fisher, 1997, page 338, I.B. Tauris Publishers,
  47. Qur'an, Chapter 17, Verse 106
  48. Quran, Chapter 97
  49. Rampton, Mike (19 October 2019). "A Deep Dive Into Incubus' Pardon Me Video". kerrang.com.
  50. Jarman, Douglas (1983). "Alban Berg, Wilhelm Fliess and the Secret Programme of the Violin Concerto". The Musical Times. 124 (1682): 218–223. doi:10.2307/962034. JSTOR   962034.
  51. Jarman, Douglas (1985). The Music of Alban Berg. University of California Press. ISBN   978-0-520-04954-3.
  52. 23 (1998) – Hans-Christian Schmid | Synopsis, Characteristics, Moods, Themes and Related | AllMovie , retrieved 12 August 2020
  53. L: Change the World (2008) – Hideo Nakata | Synopsis, Characteristics, Moods, Themes and Related | AllMovie , retrieved 12 August 2020
  54. The Number 23 (2007) – Joel Schumacher | Synopsis, Characteristics, Moods, Themes and Related | AllMovie , retrieved 12 August 2020
  55. "Nan Cross: Supported men resisting apartheid conscription". Sunday Times. 22 July 2007. Retrieved 4 March 2023 via PressReader.