id:A144922 - OEIS Search Results

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Numbers n such that n*sigma_2(n)/sigma_1(n) is an integer

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	OFFSET	`1,2`
	COMMENT	`n*A001157(n)/A000203(n) is an integer. This sequence is connected closely with Ore divisor numbers (A001599) and RMS numbers (A140480).`
	CROSSREFS	`Cf. A000203, A001157, A001599, A140480` `Sequence in context: A024675 A163656 A100915 this_sequence A088765 A078782 A165897` `Adjacent sequences: A144919 A144920 A144921 this_sequence A144923 A144924 A144925`
	KEYWORD	`easy,nonn`
	AUTHOR	`Ctibor O. Zizka (c.zizka(AT)email.cz), Sep 25 2008`

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Last modified December 18 21:37 EST 2009. Contains 171024 sequences.

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