Definition: 7.06: Even Number
An even number is one (which can be) divided in half.
Notes
 Euclid's definition of even numbers is not exact since it allows e.g. incommensurable numbers being divided into halves to be even numbers, which is obviously not correct.
Modern Formulation
see even number.
Mentioned in:
Chapters: 1
Definitions: 2 3 4
Motivations: 5
Problems: 6 7 8 9
Proofs: 10 11 12 13 14 15 16 17 18
Propositions: 19 20 21 22 23 24
Sections: 25
Solutions: 26 27
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016