id:A103288 - OEIS Search Results

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Numbers n such that sigma(n) >= 2n-1 (union of perfect, abundant and least deficient numbers).

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	OFFSET	`1,2`
	COMMENT	`If the only least deficient numbers are the powers of 2 (open problem) then this sequence is a union of A023196 and A000079.`
	FORMULA	`Such n that A004125(n) <= A004125(n-1)`
	PROGRAM	`(PARI) for(n=1, 1000, if(sigma(n)>=2*n-1, print(n)));`
	CROSSREFS	`Cf. A023196, A023197, A023198, A023199, A000079, A004125.` `Sequence in context: A090404 A058825 A087086 this_sequence A125225 A092903 A005153` `Adjacent sequences: A103285 A103286 A103287 this_sequence A103289 A103290 A103291`
	KEYWORD	`nonn`
	AUTHOR	`Max Alekseyev (maxale(AT)gmail.com), Jan 28 2005`

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Last modified December 15 00:47 EST 2009. Contains 170825 sequences.

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