id:A140221 - OEIS Search Results

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A number n is included if n is coprime to sum{k=1 to n} d(k), where d(k) is the number of divisors of k.

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	OFFSET	`1,2`
	COMMENT	`sum{k=1 to n} d(k) = sum{k=1 to n} floor(n/k) = A006218(n).`
	LINKS	`Leroy Quet, Home Page (listed in lieu of email address)`
	CROSSREFS	`Cf. A006218, A050226, A140222.` `Sequence in context: A098863 A053960 A114056 this_sequence A046668 A047533 A060525` `Adjacent sequences: A140218 A140219 A140220 this_sequence A140222 A140223 A140224`
	KEYWORD	`nonn`
	AUTHOR	`Leroy Quet May 12 2008`
	EXTENSIONS	`More terms from Max Alekseyev (maxale(AT)gmail.com), May 10 2009`

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Last modified November 23 17:09 EST 2009. Contains 167438 sequences.

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