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A072891
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The 5-cycle of the n => sigma(n)-n process, where sigma(n) is the sum of divisors of n (A000203).
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3
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OFFSET
| 1,1
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COMMENTS
| Called a "sociable" chain.
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REFERENCES
| P. Poulet, Parfaits, amiables et extensions, Editions Stevens, Bruxelles, 1918.
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FORMULA
| a(5+n)=a(n).
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CROSSREFS
| Cf. A000203, A045477, A072890, A003416.
Sequence in context: A033669 A203345 A122726 * A003416 A178278 A045217
Adjacent sequences: A072888 A072889 A072890 * A072892 A072893 A072894
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KEYWORD
| fini,full,nonn
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AUTHOR
| Miklos Kristof (kristmikl(AT)freemail.hu), Jul 29 2002
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