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7 (seven;/ˈsɛvən/) is the natural number following 6 and preceding 8.
- Seven, the fourth prime number, is not only a Mersenne prime (since 23 − 1 = 7) but also a double Mersenne prime since the exponent, 3, is itself a Mersenne prime. It is also a Newman–Shanks–Williams prime, a Woodall prime, a factorial prime, a lucky prime, a happy number (happy prime), a safe prime (the only Mersenne safe prime) and the fourth Heegner number.
- Seven is the lowest number that cannot be represented as the sum of the squares of three integers. (See Lagrange's four-square theorem#Historical development.)
- Seven is the aliquot sum of one number, the cubic number 8 and is the base of the 7-aliquot tree.
- n = 7 is the first natural number for which the next statement does not hold: "Two nilpotent endomorphisms from Cn with the same minimal polynomial and the same rank are similar."
- 7 is the only dimension, besides the familiar 3, in which a vector cross product can be defined.
- 999,999 divided by 7 is exactly 142,857. Therefore, when a vulgar fraction with 7 in the denominator is converted to a decimal expansion, the result has the same six-digit repeating sequence after the decimal point, but the sequence can start with any of those six digits. For example, 1/7 = 0.142 857 142.... and 2/7 = 0.285 714 285...
In fact, if one sorts the digits in the number 142857 in ascending order, 124578, it is possible to know from which of the digits the decimal part of the number is going to begin with. The remainder of dividing any number by 7 will give the position in the sequence 124578 that the decimal part of the resulting number will start. For example, 628/7= 89 + 5/7; here 5 is the remainder, and would correspond to number 7 in the ranking of the ascending sequence. So in this case, 628/7 = 89,714285... Another example, 5238/7 = 748 + 2/7, hence the remainder is 2, and this corresponds to number 2 in the sequence. In this case, 5238/7 = 748,285714...
- A seven-sided shape is a heptagon. The regular n-gons for n ≤ 6 can be constructed by compass and straightedge alone, but the regular heptagon cannot. Figurate numbers representing heptagons (including seven) are called heptagonal numbers. Seven is also a centered hexagonal number.
- There are seven frieze groups, the groups consisting of symmetries of the plane whose group of translations is isomorphic to the group of integers.
- There are seven fundamental types of catastrophes.
- Seven is the sum of any two opposite sides on a standard six-sided die. When rolling two standard six-sided dice, seven has a 6 in 36 (or 1/6) probability of being rolled (1–6, 6–1, 2–5, 5–2, 3–4, or 4–3), the greatest of any number.
- The Millennium Prize Problems are seven problems in mathematics that were stated by the Clay Mathematics Institute in 2000. Currently, six of the problems remain unsolved.
In quaternary, 7 is the smallest prime with a composite sum of digits.
|7 ÷ x
|x ÷ 7
Evolution of the glyph
In the beginning, various Hindus wrote 7 more or less in one stroke as a curve that looks like an uppercase J vertically inverted. The western Ghubar Arabs' main contribution was to make the longer line diagonal rather than straight, though they showed some tendencies to making the character more rectilinear. The eastern Arabs developed the character from a 6-look-alike into an uppercase V-look-alike. Both modern Arab forms influenced the European form, a two-stroke character consisting of a horizontal upper line joined at its right to a line going down to the bottom left corner, a line that is slightly curved in some font variants. As is the case with the European glyph, the Cham and Khmer glyph for 7 also evolved to look like their glyph for 1, though in a different way, so they were also concerned with making their 7 more different. For the Khmer this often involved adding a horizontal line above the glyph. This is analogous to the horizontal stroke through the middle that is sometimes used in handwriting in the Western world but which is almost never used in computer fonts. This horizontal stroke is, however, important to distinguish the glyph for seven from the glyph for one in writings that use a long upstroke in the glyph for 1.
On the seven-segment displays of pocket calculators and digital watches, 7 is the number with the most common glyph variation (0, 6 and 9 also have variant glyphs). Most calculators use three line segments, but on Sharp, Casio, and a few other brands of calculators, 7 is written with four line segments because, in Japan and Korea, 7 is written as ① in the illustration to the right.
While the shape of the 7 character has an ascender in most modern typefaces, in typefaces with text figures the character usually has a descender, as, for example, in .
Most people in Continental Europe, Latin America, and New England write 7 with a line in the middle ("
7"), sometimes with the top line crooked. The line through the middle is useful to clearly differentiate the character from the number one, as these can appear similar when written in certain styles of handwriting. This glyph is used in official handwriting rules for primary school in Russia, Ukraine, Romania and other Slavic countries.
Automotive and transportation
Commerce and business
- 7-Eleven is the trading name of a chain of convenience stores based in the U.S.
- Seven Jeans, also known as Seven '7' for all Mankind, a brand of designer jeans.
Food and beverages
- 7UP is the name of a popular soft drink.
Media and entertainment
Games (other than video games)
- Lotto Super 7, a Canadian-lottery game that had its final drawing September 18, 2009.
- Sevens, a card game
- As You Like It by William Shakespeare's contains Shakespeare's 7 Ages of Man theory.
- In Beloved (novel) by Toni Morrison the number seven seems to have recurring significance, Beloved has seven letters, 124 adds up to seven, each chapter begins on a number containing seven, and the second chapter contains seven parts.
- The original British version of Anthony Burgess' novel A Clockwork Orange is split in to three sections of seven chapters.
- In the first of the three Deltora Quest series of books by Emily Rodda, the protagonist must collect the seven gems of the fabled Belt of Deltora: topaz, ruby, opal, lapis lazuli, emerald, amethyst, and diamond. Each of the seven gems are guarded by one of seven guardians located in one of the seven locations around Deltora: The Forests of Silence, Lake of Tears, City of the Rats, The Shifting Sands, Dread Mountain, Maze of the Beast, and Valley of the Lost.
- The manga Eureka Seven, based on the anime series
- In Fist of the North Star (Hokuto no Ken), the main character, Kenshiro, is also known as "the man with seven wounds" for the seven scars on his body in the shape of the Big Dipper.
- In the Fushigi Yuugi manga series, the four beast gods each have seven warriors, the Genbu Seven, the Byakko Seven, the Seiryuu Seven, and the Suzaku Seven.
- In the Harry Potter series of novels by J.K. Rowling, seven is said to be the most powerfully magical number. There are a number of references to seven in Harry Potter: there are a total of seven books in the series; Ginny Weasley is the seventh child and only daughter of the Weasley family; Harry Potter was born in July, the seventh month of the year; Wizarding students must complete seven years of school at Hogwarts; There are seven secret passages leading out of Hogwarts; Seven is also the number on the back of Harry Potter's Quidditch robes (Prisoner of Azkaban movie). Professor Moody was also hidden in a chest with an underground cubby, which was locked with seven locks Harry Potter and the Goblet of Fire. In Quidditch each team consists of seven players. Chapter four of Book 7 is titled "The Seven Potters". Lord Voldemort succeeded in making seven Horcruxes (objects containing parts of his soul.)
- In the InuYasha series, the Shichinintai are, as their name says, a band of seven mercenaries.
- The Seven Rings of the Vongola Family in Katekyo Hitman Reborn: Sky, Storm, Rain, Sun, Thunder, Mist, and Cloud.
- In The Lost Years of Merlin series, a book is titled "The Seven Songs of Merlin"
- The character 7 (Nana) and the organization Septimal Moon in Loveless (manga)
- In the "Nana manga series, there are many recurrent instances of the number seven ("nana" is the Japanese numeral for the English "seven"), including the name of both main characters.
- Team 7 consists of the main characters in Naruto: Naruto Uzumaki, Sasuke Uchiha, Kakashi Hatake, and Sakura Haruno. Later in the series, Sai joined team 7 after Sasuke left Konohagakure.
- In the One Piece series, the Shichibukai (literally, "Seven Military Seas", known in the English versions as the "Seven Warlords of the Sea") are seven powerful pirates who work for the government.
- The Saga of Seven Suns, a series of seven novels by Kevin J. Anderson.
- In Neil Gaiman's Sandman series, there are 7 Endless: Destiny, Death, Dream, Destruction, Despair, Desire and Delirium.
- The Secret Seven, name of a children's adventure book by Enid Blyton
- In the Septimus Heap series, Septimus Is the seventh son of a seventh son, 7 is believed to be the most magykal number. There will also be 7 books in the series, along with many other things relating to the number 7.
- Aleksis Kivi's "Seven Brothers", the most famous book of Finnish literature
- The Seven Dials Mystery by Agatha Christie
- The Seven Habits of Highly Effective People, a book by Stephen Covey
- Seven Pillars of Wisdom, a book written by T.E. Lawrence
- The book Seven Years in Tibet
- In The Silmarillion, also a Tolkien work, there are seven Lords of the Valar, and seven Ladies of the Valar; Fëanor, a central character, has seven sons: Maedhros, Maglor, Celegorm, Curufin, Caranthir, Amrod, and Amras.
- In George R.R. Martin's A Song of Ice and Fire, seven gods, the Mother, the Father, the Warrior, the Crone, the Smith, the Maiden, and the Stranger, are worshipped in the land of Westeros, which is made up of seven former kingdoms and often called the Seven Kingdoms. The Seven are the primary deities of Westeros.
- In W.E.B. Du Bois's book The Souls of Black Folk, he refers to "the Negro" as "the seventh son".
- In The Tales of Alvin Maker, an alternate history fantasy series by Orson Scott Card, seventh sons are imbued with special powers, referred to as "knacks", over the physical world. The powers of a seventh son of a seventh son, the birthright of the series' main character, Alvin Smith, are especially pronounced. Men who wield these powers to create are referred to as "Makers."
- In Toaru Majutsu no Index, there are a total of seven Level 5 ESPers: Accelerator, Kakine Teitoku, Misaka Mikoto, Mugino Shizuri, The Queen of Tokiwadai, an unknown ESPer and Sogiita Gunha.
- In The Two Towers, the second volume of J.R.R. Tolkien's The Lord of the Rings, the following poem appears: "Tall ships and tall kings/Three times three/What brought they from the foundered land/Over the flowing sea?/Seven stars and seven stones/And one white tree." The "foundered land" is Númenor, and the "Seven Stars" are unknown, but they may refer to a constellation, the Sickle of the Valar. The Seven Stones are the palantíri, the seeing-stones. The number seven was also significant to Dwarvish culture as portrayed by Tolkien: there were seven fathers of the Dwarves (as recounted in The Silmarillion) and the Dwarves were later given seven rings by Sauron (according to The Lord of the Rings).
- David Eastis authored two books about the popular number seven both with the title "7".
- Jackie Leo wrote "Seven".
- We are Seven by William Wordsworth
- in The Owl Keeper the owl keeper (by Christine Brodien-Jones) is said to be born on the 7th day of the 7th month at 7 past midnight.
- 7 is a 2003 Enrique Iglesias album.
- 7, Mick Thompson, is one of the guitarists for popular metal band Slipknot.
- Sweet 7, a Sugababes album
- In the NHL, MLB, and NBA, the maximum number of games played in a playoff series.
- The jersey number 7 has been retired by several North American sports teams in honor of past playing greats or other key figures:
- Football and soccer
- Frisbee and Ultimate Frisbee
- Motor sports
- Rugby league
- The jersey number 7 is worn by the starting scrum-half/halfback in most competitions (but not in the European Super League, which uses static squad numbering).
- Rugby union
- The jersey number 7 is worn by the starting openside flanker. (Some teams use "left" and "right" flankers instead of "openside" and "blindside", with 7 being worn by the starting right flanker.)
- A converted try is worth 7 points. This number is also significant because the standard bonus points system used in most competitions awards 1 bonus point to a team that loses by 7 points or less.
- The IRB Sevens World Series, an annual competition for national teams in rugby union sevens (see below)
- The Rugby World Cup Sevens, the World Cup for the union version of Sevens
- Rugby sevens, a variant of union and league that contains only seven players per side instead of the standard 15 (union) or 13 (league)
- Track and field
Networks and stations
- 7 Days, a comedy gameshow based on news stories from New Zealand.
- The name of a television show 7th Heaven
- The name of a The Adventures of Super Mario Bros. 3 cartoon, 7 Continents for 7 Koopas.
- Blake's Seven was a BBC science fiction series that ran from 1978 to 1981
- Eureka Seven, a science fiction and romance anime.
- Seven, an episodic character from the sitcom Married... with Children.
- In the Seinfeld episode "The Seven", Seven is the name George Costanza desires to give his first-born, having allegedly promised this to the widow of baseball great Mickey Mantle (whose uniform number was 7). George is enraged, however, when his fiance's cousin and spouse copy the idea and give the name to their child.
- Seven Days, a science fiction show about the NSA using time travel.
- The name of one of the monsters in the cartoon television show Seven Little Monsters
- In Star Trek: Voyager, Seven of Nine (also called Seven for short) is one of the crewmembers
- The Ultra Series has two heroes with "Seven" in their name: Ultra Seven and Ultra Seven-21.
- Ultra Seven, a television series aired in 1967, and the superhero of the same name. He is the honorary seventh member of the Ultra Garrison
- in House of Anubis (on nick)the "chosen one" has to be born on 7/7 (July 7) at 7:00am
- The 7th Guest, produced by Trilobyte and released by Virgin Games in 1993, is an FMV-based puzzle horror video game.
- In the Ace Attorney series, 7 is a recurring number. For example: there is a 7 year age gap between the main character and his assistant, there is a 7-year gap between the plots of Ace Attorney 3 and 4, Godot's favorite coffee blend is #107, the Chief of police, Gant's keycard number is 7777777.
- In Final Fantasy VII, if anyone in your party's HP reaches to 7777, they will go berserk and strike the opponent a number of times at a damage rate of 7777. This is called the Lucky 7's. After the battle, however, the character's HP will be reduced to 1 to prevent this state from rolling over to another battle. There is also a bar in the Final Fantasy VII game series named "Seventh Heaven". Final Fantasy VII is also the seventh game in the Final Fantasy series.
- Puyo Puyo 7 is the seventh game in the Puyo Puyo series.
- 7 is a number used many times by Bungie Studios in their Halo series and Marathon trilogy. 7 appears in a variety of different contexts, from the stories of the games to the raw game coding also, the main character, The Master Chief, also known as John-117; has a call sign of 117 and, 1x1x7=7 or 11x7=77. Also, in the Myth Series the Fallen Lords are seven: Balor, Soulblighter, Shiver, the Deceiver, the Watcher, and two other unknown Fallen). There is also a pass of the Cloudspines called Seven Gates. Additionally, the Myth timeline recognizes [i]seven[i] ages: The Creation Age (when the world was created), the Age of the Trow (the golden age of the Trow), the Axe Age (when the Free Cities of the North were raised), the Age of Reason a.k.a. the Second Age (when Tireces defeated Sorongath the Flayed and returned as Moagim the Faceless Terror and released the Myrkridia to the world), the Wind Age a.k.a. the Third Age, from the coming of the Myrkiridia to their biding into the Tain), the Wolf Age a.k.a. the Fourth Age a.k.a. the Age of Light, from the imprisonment of the Mrrkridia to the devastation of Muirthemne by the Fallen Lords), and the Sword Age (the age in which Myth: The Fallen Lords and Myth II: Soulblighter take place).
- In the Eidos Studios Legacy of Kain series game Legacy of Kain: Soul Reaver, there are seven main vampires: Kain, Raziel, Turel, Dumah, Rahab, Zephon, and Melchaiah.
- The 7 is a group of deadly mercenaries that kidnap the protagonist's family in the video game Kane & Lynch: Dead Men.
- In the Killer7 game, the number of individual personalities serving Harman Smith as part of the group of assassins called the Killer7
- In Kingdom Hearts, there are seven Princesses of Heart (Snow White, Cinderella, Alice, Aurora, Belle, Jasmine, and Kairi (the only original characters among them)). Seven (VII) is also the number of the character Saïx, a member of the antagonists Organisation XIII from Kingdom Hearts II.
- Nintendo's Super Mario video game franchise:
- Nana (One of two Japanese readings for "seven" and also a common feminine name) is one of the supporting characters in Mega Man X: Command Mission. Nana is also Popo's partner in Ice Climbers.
- In Sega's Sonic the Hedgehog video game franchise, there are often seven Chaos Emeralds
- In Valkyria Chronicles, you control Squad 7 of the militia force.
- In The World Ends with You, one of the antagonists is a musician called "777."
- The Legend of Zelda franchise:
Seven Days of Creation - 1765 book
The number seven (7) in the seven days of Creation is typological and the number seven appears commonly elsewhere in the Bible. These include:
- Seven days of Creation (Genesis 1) e.g., God rested on and sanctified the seventh day (Sabbath)
- Anyone who dares to kill Cain 'will suffer vengeance seven times over' (Genesis 4:15)
- Lamech in his "Song of the Sword" claims that 'if Cain shall be avenged sevenfold', he himself shall be 'seventy-sevenfold' (Genesis 4:24)
- Seven years of plenty and seven years of famine in Pharaoh's dream (Genesis 41)
- In regards to the sin sacrifice, the anointed priest was to sprinkle the bullock's blood seven times before the lord (Leviticus 4:6)
- Seven days of the feast of Passover (Exodus 13:3–10)
- Seven day week and the pattern concerning distribution and use of manna (Exodus 16)
- The Menorah (Hebrew: מנורה), is a seven-branched candelabrum lit by olive oil in the Tabernacle and the Temple in Jerusalem (Exodus 25)
- Seven year cycle around the years of Jubilee (Leviticus 25)
- Jericho's walls fall on the seventh day after seven priests with seven trumpets march around the city seven times (Joshua 6:8)
- Seven things that are detestable to the LORD (Proverbs 6:16–19)
- Seven Pillars of the House of Wisdom (Proverbs 9:1)
- Seven loaves multiplied into seven basketfuls of surplus (Matthew 15:32–37)
- Peter asked Jesus if he should forgive those who sinned against him up to 7 times; Jesus responded by saying to forgive them 'seventy times seven times', remembering so the curse of Cain and the song of Lamech in Genesis 4.
- The seven last words (or seven last sayings) of Jesus on the cross
- Seven men of honest report, full of the Holy Ghost and wisdom (Acts 6:3)
- In the Book of Revelation, seven is a central figure of quantities: Seven Spirits of God, Seven Churches (to which the book is addressed);
- Seven of the following appear in Revelation: golden lampstands(1:12), stars(1:16), torches of fire(4:5) seals(5:1), angels and their trumpets(8:2), last plagues(15:1), golden bowls(15:7), thunders(10:3), horns and eyes(5:6), diadems(12:3) and kings(17:10). See Category:Seven in the Book of Revelation.
Other sevens in Christian knowledge and practice include:
- The Seven Corporal Acts of Mercy and Seven Spiritual Acts of Mercy of Roman Catholic, Anglican, and other traditions
- The Seven deadly sins: lust, gluttony, greed, sloth, wrath, envy, and pride
- Seven Gifts of the Holy Spirit
- The Seven Joys of the Virgin Mary, of Roman Catholic, Anglican, and other traditions
- The Seven Sacraments in the Catholic faith (though some traditions assign a different number)
- The Seven Sorrows of the Virgin Mary, of Roman Catholic, Anglican, and other traditions
- There are seven suicides mentioned in the Bible (OT and NT).
- The seven terraces of Mount Purgatory (one per deadly sin)
- The Seven Virtues: chastity, temperance, charity, diligence, kindness, patience, and humility
- In the genealogy in the Gospel of Luke, Jesus is 77th in a direct line
- The number of heads of the three beasts (7 × 10 × 7 + 7 × 10 × 10 + 7 × 10 = 1260) of the Book of Revelation, and of some other monsters, like the hydra and the number of seals
- The Sanskrit word sapta refers to number seven.
- Indian Music has "Saptak Swaras," seven octats (sa re ga ma pa dha ni) which are basics of music, using which hundreds of Ragas are composed.
- Celestial group of seven stars are named as "Sapta Rishi" based on the seven great saints.
- Seven Promises, Seven Rounds in Hindu Wedding and Seven Reincarnation
- According to Hinduism, there are seven worlds in the universe, seven seas in the world and seven Rishies (seven gurus) called sapta rishis.
- Seven hills at tirumala also known as ezhu malaiyan means Sevenhills god
- There are 7 Chakras in the basic model used in various eastern traditions and philosophies.
- The number of ayat in surat al-Fatiha
- The number of layers of the Earth in Islamic religion is seven
- The number of skies in Islamic religion is seven
- The number of circumambulations (Tawaf) that are made around the Kaaba
- The number of walks between Al-Safa and Al-Marwah mountains—that is travelling back and forth—seven times during the ritual pilgrimages of Hajj and Umrah
- The number of heavens in Islamic religion, i.e. levels in heaven.
- The number of hells in hell is also seven i.e. levels in hell.
- The number of doors to hell is seven (for heaven the number of doors is eight).
- In Verse 12:46 (see Islamic view of Joseph) of the Quran, Joseph (Yusef) is asked to interpret the King's dream where seven fat cows were dreamt to have been devoured by seven skinny cows and seven green spikes, and others shrivelled.
- The number of the big sins or vices is seven which are from a Hadith of the prophet Mohamed : "Avoid the seven sins polytheism, witchcraft, the killing of the soul which Allah has forbidden except by right, consuming riba, consuming the wealth of the orphan, to escape from the battles and slandering chaste women"
- Shiv`a (another pronunciation of the Hebrew word for 7—(Hebrew: שבעה ; "seven")), is the number of days of mourning. Hence, one sits Shiva. As in Shiva (Judaism)
- The weekly Torah portion is divided into seven aliyahs, and seven Jewish men (or boys over the age of 13 who are considered men; Bar Mitzvah) are called up for the reading of these aliyahs during Shabbat morning services.
- Seven blessings are recited under the chuppah during a Jewish wedding ceremony.
- A Jewish bride and groom are feted with seven days of festive meals after their wedding, known as Sheva Berachot ("Seven Blessings").
- The number of Ushpizzin (also known as the "Seven Shepherds") who visit the sukkah during the holiday of Sukkot: Abraham, Isaac, Jacob, Joseph, Moses, Aaron, and David.
- The number of nations God told the Israelites they would displace when they entered the land of Israel (Deut. 7:1): the Hittite, the Girgashite, the Amorite, the Canaanite, the Perizzite, the Hivite, and the Jebusite.
- In Breslov tradition, the seven orifices of the face (2 eyes, 2 nostrils, 2 ears, and the mouth) are called "The Seven Candles."
- The 7 Sephirot of primary conscious emotion that are attributes of the creator.
- Deity, being, or character
- The Seven Lucky Gods refer to the seven gods of good fortune in Japanese mythology.
- The number of archangels according to some systems.
- In Buddhism, Buddha walked 7 steps at his birth.
- In Khasi mythology, the seven divine women who were left behind on earth and became the ancestresses of all humankind.
- The number of sleeping men in the Christian myth of the "Seven Sleepers."
- The number of sages in Hindu mythology; their wives are the goddesses referred to as the "Seven Mothers."
- In Iran, German, Spanish, and other cultures that speak Romance Languages, cats are said to have 7 lives as opposed to English, where cats are said to have 9 lives.
- In Irish mythology, the epic hero Cúchulainn is associated with the number 7. He has 7 fingers on each hand, 7 toes on each foot, and 7 pupils in each eye. In the Irish epic Táin Bó Cúailnge, Cúchulainn is 7 years old when he receives his first weapons and defeats the armies of the Ulaidh and his son Connla is 7 years old when he is slain by Cúchulainn in "The Death of Aife's Only Son."
- In Galician folklore, a seventh son will be a werewolf. In other folklores, after six daughters, the seventh child is to be a son and a werewolf. In other European folklores, the seventh son of a seventh son will be a child with special powers of healing and clairvoyant seeing, and in other cultures that seventh son of a seventh son would be a vampire.
- In Guaraní mythology, the number of prominent legendary monsters.
- In the eponymous British folk tale, Thomas the Rhymer went to live in the faerie kingdom for 7 years.
- The number of main islands of mythological Atlantis.
- The number of gateways traversed by Inanna during her descent into the underworld.
- Cibola was one of the legendary Seven Cities of Gold the Spanish thought existed.
- In the Bahá'í faith, the text The Seven Valleys, by the Prophet-Founder Bahá'u'lláh, relates the journey of the soul through the seven "valleys" of Search, Love, Knowledge, Unity, Contentment, Wonderment, and finally True Poverty and Absolute Nothingness.
- Thing, concept, or symbol
- The number of daughters of Atlas in the Pleiades (also called the "Seven Sisters")
- The number of stellar objects in the solar system visible to the naked eye from Earth – the Sun, the Moon and the five classical naked eye planets: Mars, Mercury, Jupiter, Venus, and Saturn.
- Messier object M7, a magnitude 3.5 open cluster in the constellation Scorpius.
- The New General Catalogue object NGC 7, a 14th magnitude spiral galaxy in the constellation Sculptor.
- The number of saints appearing in a constellation called "Saptharishi Mandalam" in Indian astronomy.
- The number of main stars in the constellations of the Big Dipper and Orion.
- The Saros number of the solar eclipse series which began on -2590 April 8 and ended on -1310 May 16. The duration of Saros series 7 was 1,280.1 years, and it contained 72 solar eclipses.
- The Saros number of the lunar eclipse series which began on -2595 July 15 and ended on -1008 February 22. The duration of Saros series 7 was 1,586.6 years, and it contained 89 lunar eclipses.
- The Roman numeral VII stands for white dwarfs in the Yerkes spectral classification scheme.
- The Roman numeral VII (usually) stands for the seventh-discovered satellite of a planet or minor planet (e.g., Jupiter VII).
Isaac Newton's 7 colors of the rainbow
- There are 7 SI base units. These are a coherent set of units defined to measure 7 basic physical properties: metre, kilogram, second, ampere, kelvin, mole, candela. The 7 SI base units are used to define all other SI units, which are known as SI derived units.
- Isaac Newton identified 7 colors of the rainbow – red, orange, yellow, green, blue, indigo, and violet
Temporal, seasonal, and holidays
- The seven days of the week
- The Kulin people of Australia living near the Dandenong Ranges traditionally have seven seasons. Some of the Native Americans of Montana also have seven seasons: chinook season, muddy spring, green summer, gold summer (or dry summer), "Indian" Summer, late fall, and cold winter.
- The United States declared Independence in the 7th month of 1776.
- The Heptarchy, from the (Greek for seven realm, is the name applied by historians to the period (500–850 CE) in English history after the Anglo-Saxon conquest of England, derived from the seven kingdoms of Northumbria, Mercia, East Anglia, Essex, Kent, Sussex, and Wessex, which eventually merged to become the Kingdom of England during the early 10th century.
- September was the seventh month in the ancient Roman calendar, as its name indicates. After the reform that led to the current order, the seventh month is July.
- Septidi was the seventh day of the decade in the French Revolutionary Calendar.
- The 7th glyph of the Maya Calendar is Blue Hand, it represents the days in creation and is associated with creative perfection. This is the glyph of the last day of their calendar that ends on December 21, 2012.
Software and technology
- 7 is the calling code of Russia. Only the North American Numbering Plan (+1) and Russia (+7) have a single-digit code.
- Windows 7, the latest release of Windows series of operating systems from Microsoft.
- Video game developer Bungie, famed for the Halo series of games, often references the number seven in their products.
Seven is also
- The number of basic principles of the bushido
- The number of chakras
- One of two single-digit numbers that has two syllables, the other being Zero.
- ^ Bryan Bunch, The Kingdom of Infinite Number. New York: W. H. Freeman & Company (2000): 82
- ^ Georges Ifrah, The Universal History of Numbers: From Prehistory to the Invention of the Computer transl. David Bellos et al. London: The Harvill Press (1998): 395, Fig. 24.67
- ^ Eeva Törmänen (8.9.2011). "Aamulehti: Opetushallitus harkitsee numero 7 viivan palauttamista" (in Finnish). Tekniikka & Talous. http://www.tekniikkatalous.fi/viihde/aamulehti+opetushallitus+harkitsee+numero+7+viivan+palauttamista/a682831.
- ^ "Education writing numerals in grade 1."(Russian)
- ^ 21Then Peter came to Jesus and asked, 'Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?' 22Jesus answered, 'I tell you, not seven times, but seventy times seven.'
- ^ Bible.org: Sermon Illustrations
- ^ Encyclopædia Britannica "Number Symbolism"
- ^ "SI brochure, The seven SI base units". http://www.bipm.org/en/si/si_brochure/chapter2/2-1/#2-1-2. Retrieved 2009-09-11.
- ^ "SI brochure, SI derived units". http://www.bipm.org/en/si/si_brochure/chapter2/2-2/2-2-1.html. Retrieved 2009-09-11.