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Least k <= n such that n*sigma(k) = k*sigma(n), where sigma(n) is the sum of divisors of n (A000203).

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	OFFSET	`1,2`
	COMMENT	`Conjecture: There are infinitely many terms such that a(n)<n. A050973 has those n, A050972 has the a(n).`
	PROGRAM	`(PARI) for(n=1, 74, s=sigma(n); k=1; while(nsigma(k)!=ks, k++); print1(k, ", "));`
	CROSSREFS	`Cf. A050972, A050973, A094757, A094758, A000203.` `Cf. A095301 for n such that a(n) < n.` `Sequence in context: A025484 A030545 A137317 this_sequence A030542 A158377 A008684` `Adjacent sequences: A094756 A094757 A094758 this_sequence A094760 A094761 A094762`
	KEYWORD	`nonn`
	AUTHOR	`Amarnath Murthy (amarnath_murthy(AT)yahoo.com), May 30 2004`
	EXTENSIONS	`Edited and extended by Don Reble (djr(AT)nk.ca) and Klaus Brockhaus (klaus-brockhaus(AT)t-online.de) May 31 2004`

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.

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