User talk:Mgao

Your divisibility rule for powers of 3 is wrong. Consider 1899, whose digits sum to 27 but which is not divisible by 27. --JBL 10:23, 19 July 2006 (EDT)

Do not copy from Wikipedia. (See Policies and guidelines.) Also, when you add something to the Wiki, you should look it over afterwards -- in particular, nearly all the Latex in your post on Bretschneider's formula could not be processed by the Wiki. --JBL 09:06, 2 December 2006 (EST)

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