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oblong number
Directory
References
Images
Oblong numbers formed by doubling triangular numbers
Discover
Figure 13: A Maxim machine gun, belt-fed and water-cooled, operated by German infantrymen, World War I.
7 Deadliest Weapons in History
Aspirin pills.
7 Drugs that Changed the World
Poker game. Card game. Royal Flush in poker. Hearts suit gambling
Poker Hands Ranked
Cathedrale St.Jean in Lyon, France has a 14th-century astronomical clock that shows religious feast days till the year 2019; Perpetual Calendar
Ten Days That Vanished: The Switch to the Gregorian Calendar
Aurochs. Bos primigenius. Skeleton. Extinct animal. Skeleton of an Aurochs, an extinct wild ox.
6 Animals We Ate Into Extinction
King Cobra snake in Malaysia. (reptile)
9 of the World’s Deadliest Snakes
Gutzon Borglum. Presidents. Sculpture. National park. George Washington. Thomas Jefferson. Theodore Roosevelt. Abraham Lincoln. Mount Rushmore National Memorial, South Dakota.
9 Memorials and Monuments in the United States

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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