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A072890
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The 28-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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14316, 19116, 31704, 47616, 83328, 177792, 295488, 629072, 589786, 294896, 358336, 418904, 366556, 274924, 275444, 243760, 376736, 381028, 285778, 152990, 122410, 97946, 48976, 45946, 22976, 22744, 19916, 17716, 14316
(list; graph; refs; listen; history; internal format)
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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(28+n)=a(n).
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MATHEMATICA
| f[n_]:=Plus@@Divisors[n]-n; a=7524; Table[a=f[a], {n, 0, 28}] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 01 2009]
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CROSSREFS
| Cf. A000203, A045477, A072891.
Sequence in context: A115554 A106726 A064965 * A049442 A106725 A190469
Adjacent sequences: A072887 A072888 A072889 * A072891 A072892 A072893
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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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