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A094759
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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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3
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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 6, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Conjecture: There are infinitely many terms such that a(n)<n. A050973 has those n, A050972 has the a(n).
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PROG
| (PARI) for(n=1, 74, s=sigma(n); k=1; while(n*sigma(k)!=k*s, k++); print1(k, ", "));
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CROSSREFS
| Cf. A050972, A050973, A094757, A094758, A000203.
Cf. A095301 for n such that a(n) < n.
Sequence in context: A025484 A030545 A137317 * A030542 A158377 A167975
Adjacent sequences: A094756 A094757 A094758 * A094760 A094761 A094762
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KEYWORD
| nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), May 30 2004
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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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