Editing 263 (section)

== Events ==
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=== By place ===

==== Roman Empire ====
* King [[Odenathus]] of [[Palmyra]] declares himself ruler of the area west of the  [[Euphrates|River Euphrates]] and is declared ''Dux Orientalis'' by the Roman emperor [[Gallienus]].

==== Asia ====
* [[Conquest of Shu by Wei]]: The Chinese state of [[Cao Wei]] conquers [[Shu Han]], one of its two rival states.
* [[Sima Zhao]], regent of the [[Cao Wei]] state, receives and accepts the [[nine bestowments]], state chancellorship, and the title ''Duke of Jin'' from [[Cao Huan]].

=== By topic ===

==== Art and Science ====
* Chinese mathematician [[Liu Hui]] writes a commentary on ''[[The Nine Chapters on the Mathematical Art]]'', describing what will later be called [[Gaussian elimination]], computing [[pi]], etc.<ref>{{Cite book |last=Needham |first=Joseph |url=https://books.google.com/books?id=jfQ9E0u4pLAC |title=Science and Civilisation in China: Volume 3, Mathematics and the Sciences of the Heavens and the Earth |publisher=Cambridge University Press |year=1959 |location=Cambridge, England |pages=30|isbn=978-0-521-05801-8 }}</ref>
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