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oblong number
Directory
References
Images
Oblong numbers formed by doubling triangular numbers
Discover
Lake Mead (the impounded Colorado River) at the Hoover Dam. The light-coloured band of rock above the shoreline shows the decrease in water level in the first few years of the 21st century.
6 Lakes That Are Drying Up
illustration of the walking titanosaurus, Patagotitan mayorum
Titanosaurs: 8 of the World's Biggest Dinosaurs
Estimated battle casualties, Normandy invasion, World War II. WWII, D-Day
Estimated Battle Casualties During the Normandy Invasion and Campaign to Liberate Paris (June–August 1944)
Time zone map with standard time zones and International Date Line
Why Are Some Time Zones 30 Minutes Off Instead of an Hour?
Portion of the Aleppo Codex, a manuscript of the Hebrew Bible written in the Hebrew language in the 10th century CE; in the Shrine of the Book, Israel Museum, Jerusalem.
Why Do Languages Die?
Rainbow flag. Sign of diversity, inclusiveness, hope, yearning. Gay pride flag popularized by San Francisco artist Gilbert Baker in 1978. Inspired by Judy Garland singing Over the Rainbow. gay rights, homosexual, gays, LGBT community
13 LGBTQ Writers You Should Read
airplane in flight (plane, aircraft, flying)
7 Puzzling Plane Disappearances

oblong number

mathematics

Learn about this topic in these articles:

definition and properties

  • See an explanation on Zeno's Achilles paradox, an infinite series concept used in finance to pay off mortgages
    In number game: Polygonal and other figurate numbers

    Oblong numbers are the numbers of dots that can be placed in rows and columns in a rectangular array, each row containing one more dot than each column. The first few oblong numbers are 2, 6, 12, 20, and 30. This series of numbers is…

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