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'''85''' is:
'''85''' is:


* the product of two [[prime number]]s (5 and 17), and is therefore a [[semiprime|biprime]]; specifically, the 24th biprime not counting perfect squares. Together with 86 and 87, it forms the second cluster of three consecutive biprimes.
* the product of two [[prime number]]s (5 and 17), and is therefore a [[semiprime]] of the form (5.q) where q is prime.
* specifically, the 24th [[Semiprime]], it being the fourth of the form (5.q).
* an [[octahedral number]].<ref>{{Cite web|url=https://oeis.org/A005900|title=Sloane's A005900 : Octahedral numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
*together with [[86 (number) |86]] and [[87 (number)|87]], forms the second cluster of three consecutive [[semiprimes]]; the first comprising [[33 (number)|33]], [[34 (number)|34]], [[35 (number)|35]].<ref>{{Cite OEIS|A056809|Numbers k such that k, k+1 and k+2 are products of two primes}}</ref>
* a [[centered triangular number]].<ref>{{Cite web|url=https://oeis.org/A005448|title=Sloane's A005448 : Centered triangular numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
* with a prime [[aliquot sum]] of [[23 (number)|23]] in the short [[aliquot sequence]] (85,[[23 (number)|23]],[[1 (number)|1]],0).
* a [[centered square number]].<ref>{{Cite web|url=https://oeis.org/A001844|title=Sloane's A001844 : Centered square numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
* an [[octahedral number]].<ref>{{Cite OEIS|A005900|Octahedral numbers}}</ref>
* a [[decagonal number]].<ref>{{Cite web|url=https://oeis.org/A001107|title=Sloane's A001107 : 10-gonal (or decagonal) numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
* a [[centered triangular number]].<ref>{{Cite OEIS|A005448|Centered triangular numbers}}</ref>
⚫
* the smallest number that can be expressed as a [[Fermat's theorem on sums of two squares|sum of two squares]], with all squares greater than 1, in two ways, 85 = 9<sup>2</sup> + 2<sup>2</sup> = 7<sup>2</sup> + 6<sup>2</sup>.<ref>{{Cite OEIS|A007692}}. Note that the two smaller numbers on this list, 50 and 65, have 1 as one of the squares in their representations as sums of two squares.</ref>
* a [[centered square number]].<ref>{{Cite OEIS|A001844|Centered square numbers}}</ref>
⚫
* the length of the hypotenuse of four [[pythagorean triple|pythagorean triangles]].
* a [[decagonal number]].<ref>{{Cite OEIS|A001107|10-gonal (or decagonal) numbers}}</ref>
* a [[Smith number]] in decimal.<ref>{{Cite web|url=https://oeis.org/A006753|title=Sloane's A006753 : Smith numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
⚫
* the smallest number that can be expressed as a [[Fermat's theorem on sums of two squares|sum of two squares]], with all squares greater than 1, in two ways, 85 = 9<sup>2</sup> + 2<sup>2</sup> = 7<sup>2</sup> + 6<sup>2</sup>.<ref>{{Cite OEIS|A007692|Numbers that are the sum of 2 non-zero squares in 2 or more ways}}. The two smaller numbers on this list, 50 and 65, have 1 as one of the squares in their representations as sums of two squares.</ref>
⚫
* the length of the hypotenuse of four [[pythagorean triple|Pythagorean triangles]].
* a [[Smith number]] in decimal.<ref>{{Cite OEIS|A006753|Smith numbers}}</ref>


==In astronomy==
==In astronomy==
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* [[85 Pegasi]] is a multiple star system in constellation of [[Pegasus (constellation)|Pegasus]]
* [[85 Pegasi]] is a multiple star system in constellation of [[Pegasus (constellation)|Pegasus]]
* [[85 Ceti]] is a variable star in the constellation of [[Cetus]]
* [[85 Ceti]] is a variable star in the constellation of [[Cetus]]
* [[85P/Boethin]] is a periodic comet
* [[85D/Boethin]] is a periodic comet


==In titles and names==
==In titles and names==
* ''[[Federalist No. 85]]'', by [[Alexander Hamilton]], the last of ''[[The Federalist Papers]]'' (1788)
* ''[[Federalist No. 85]]'', by [[Alexander Hamilton]], the last of ''[[The Federalist Papers]]'' (1788)
* ''[[The 85 Ways to Tie a Tie]]'', a book by [[Thomas Fink]] and Yong Mao
* ''[[The 85 Ways to Tie a Tie]]'', a book by [[Thomas Fink]] and Yong Mao
* ''85 Days: The Last Campaign of Robert Kennedy'' a book by [[Jules Witcover]]
* ''85 Days: The Last Campaign of Robert Kennedy'', a book by [[Jules Witcover]]
* ''[[Live/1975–85]]'', an album of live recordings by [[Bruce Springsteen]] (1986)
* ''[[Live/1975–85]]'', an album of live recordings by [[Bruce Springsteen]] (1986)
* ''[[80–85]]'' a compilation album by [[Bad Religion]] (1991)
* ''[[80–85]]'', a compilation album by [[Bad Religion]] (1991)
* ''[[Cupid & Psyche 85]]'', an album by band [[Scritti Politti]] (1985)
* ''[[Cupid & Psyche 85]]'', an album by band [[Scritti Politti]] (1985)
* ''[[45/85]]'' was a television documentary on World War II
* ''[[45/85]]'' was a television documentary on World War II
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In [[College athletics|U.S. college athletics]], schools that are members of [[NCAA Division I]] are limited to providing [[athletic scholarship]]s to a maximum of 85 [[College football|football]] players in a given season. The specifics vary by the two Division I football subdivisions:
In [[College athletics|U.S. college athletics]], schools that are members of [[NCAA Division I]] are limited to providing [[athletic scholarship]]s to a maximum of 85 [[College football|football]] players in a given season. The specifics vary by the two Division I football subdivisions:
* In the top-level [[NCAA Division I Football Bowl Subdivision|FBS]], each player provided with a scholarship may, and almost always does, receive a full scholarship.
* In the top-level [[NCAA Division I Football Bowl Subdivision|FBS]], each player provided with a scholarship may, and almost always does, receive a full scholarship.
* In the second-level [[NCAA Division I#Football Championship Subdivision|FCS]], schools are allowed to provide football-related athletic aid equivalent to 63 full scholarships, but this aid may be divided among up to 85 players as the schools see fit.
* In the second-level [[NCAA Division I Football Championship Subdivision|FCS]], schools are allowed to provide football-related athletic aid equivalent to 63 full scholarships, but this aid may be divided among up to 85 players as the schools see fit.


==In other fields==
==In other fields==
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* The year AD 85, [[85 BC]], or 1985.
* The year AD 85, [[85 BC]], or 1985.
* The Muslim calendar year 85 AH.
* The Muslim calendar year 85 AH.
* The [[atomic number]] of [[astatine]]
* The [[atomic number]] of the chemical element [[astatine]]
* The number of the French department [[Vendée]]
* The number of the French department [[Vendée]]
* The ISBN Group Identifier for books published in [[Brazil]]
* The ISBN Group Identifier for books published in [[Brazil]]
* The radix of the [[Ascii85]] (sometimes called Base85) binary-to-text encoding
* The radix of the [[Ascii85]] (sometimes called Base85) binary-to-text encoding
* The IQ and nickname of Aaron in [[Alien 3]]
* The IQ and nickname of Aaron in ''[[Alien 3]]''
* The number worn by [[Chad Ochocinco]], whose name means "eight five" in Spanish
* The number worn by [[Chad Ochocinco]], whose name means "eight five" in Spanish
* [[Arabigere 85]] is a village in India
* [[Arabigere 85]] is a village in India
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* [[F85 (disambiguation)]], multiple uses
* [[F85 (disambiguation)]], multiple uses
* Part of the assignation for the [[Toyota AE85]], commonly referred to as an "eight-five".
* Part of the assignation for the [[Toyota AE85]], commonly referred to as an "eight-five".
* [[KiHa 85 series]] is a [[Diesel multiple unit|diesel]] [[Limited express]] train that ran in [[Japan]] until 2023.
* [[HC85 series]] is the successor of KiHa 85 and is a [[Hybrid train|hybrid]] diesel limited express train.


==In military technology==
==In military technology==
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* [[List of highways numbered 85]]
* [[List of highways numbered 85]]
* [[List of highways numbered 85A]]
* [[List of highways numbered 85A]]
* [[Type 85 (submachine gun)|Type 85]], a designation of many military equipment
* [[Type 85 submachine gun]]


==References==
==References==
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==External links==
==External links==
{{Commons category|85 (number)}}
{{Commons category}}
* [http://www.wisdomportal.com/Numbers/85-1.html 85]
* [http://www.wisdomportal.com/Numbers/85-1.html 85]
* Jorge Stolfi, [http://www.ic.unicamp.br/~stolfi/realwork/hollyconst/ The Hollywood Constant].
* Jorge Stolfi, [http://www.ic.unicamp.br/~stolfi/realwork/hollyconst/ The Hollywood Constant].

Latest revision as of 14:01, 3 June 2024

85 (eighty-five) is the natural number following 84 and preceding 86.

← 84 85 86 →
Cardinaleighty-five
Ordinal85th
(eighty-fifth)
Factorization5 × 17
Divisors1, 5, 17, 85
Greek numeralΠΕ´
Roman numeralLXXXV
Binary10101012
Ternary100113
Senary2216
Octal1258
Duodecimal7112
Hexadecimal5516

In mathematics[edit]

85 is:

In astronomy[edit]

In titles and names[edit]

In sports[edit]

In U.S. college athletics, schools that are members of NCAA Division I are limited to providing athletic scholarships to a maximum of 85 football players in a given season. The specifics vary by the two Division I football subdivisions:

  • In the top-level FBS, each player provided with a scholarship may, and almost always does, receive a full scholarship.
  • In the second-level FCS, schools are allowed to provide football-related athletic aid equivalent to 63 full scholarships, but this aid may be divided among up to 85 players as the schools see fit.

In other fields[edit]

In military technology[edit]

  • 85mm is a common caliber for cannons
  • SU-85 was a Soviet tank
  • TR-85 was a Romanian battle tank
  • Tu-85 was a prototype Soviet bomber
  • ASU-85 a Soviet self-propelled gun
  • CZ 85 is a Czech 9mm semiautomatic pistol
  • PT-85 is a Korean tank
  • 7.62 Tkiv 85 is a Finnish army rifle
  • HG 85 is a Swiss fragmentation grenade
  • Taurus Model 85, a 9mm revolver made in Brazil

See also[edit]

References[edit]

  1. ^ Sloane, N. J. A. (ed.). "Sequence A056809 (Numbers k such that k, k+1 and k+2 are products of two primes)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  2. ^ Sloane, N. J. A. (ed.). "Sequence A005900 (Octahedral numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  3. ^ Sloane, N. J. A. (ed.). "Sequence A005448 (Centered triangular numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  4. ^ Sloane, N. J. A. (ed.). "Sequence A001844 (Centered square numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  5. ^ Sloane, N. J. A. (ed.). "Sequence A001107 (10-gonal (or decagonal) numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  6. ^ Sloane, N. J. A. (ed.). "Sequence A007692 (Numbers that are the sum of 2 non-zero squares in 2 or more ways)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.. The two smaller numbers on this list, 50 and 65, have 1 as one of the squares in their representations as sums of two squares.
  7. ^ Sloane, N. J. A. (ed.). "Sequence A006753 (Smith numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.

External links[edit]

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