History of Countable/Talk

	Revision 4 . . December 10, 2001 12:21 pm by Josh Grosse
	Revision 3 . . August 22, 2001 6:55 pm by Anatoly Vorobey [answer]

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Difference (from prior major revision) (no other diffs)

Changed: 8c8,12

--AV

--AV Why would we prove the countability of Q by taking it as a countable union of countable sets? The usual way is just to present an ordering, and is much simpler, IMO. 0, 1, -1, 2, -2, 1/2, -1/2, 3, -3, 1/3, -1/3, 4, -4, 5, -5, 1/5, -1/5, 6, -6, 3/2, -3/2, 2/3, -2/3, 1/6, -1/6, ...