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A056076
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Numbers n such that n divides sigma(n) + d(n), where d(n) is the number of divisors of n and sigma(n) is their sum.
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1, 3, 14, 52, 60, 130, 184, 656, 5472, 8648, 12008, 34688, 2118656, 2500704, 33721216, 40575616, 59376256, 89397016, 99523456, 134438912, 150441856, 173706136, 283417216, 537346048, 1082640256, 6801628304, 91707741184
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(28) > 2*10^11. 14451706793984, 2258918614925312 and 9007202811510784 are also terms. - Donovan Johnson, Feb 10 2012
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MATHEMATICA
| Do[If[Mod[DivisorSigma[1, n]+DivisorSigma[0, n], n]==0, Print[n]], {n, 1, 10^8}]
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PROG
| (PARI) for(n=1, 10^8, if(Mod((sigma(n)+numdiv(n)), n)==0, print(n)))
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CROSSREFS
| Cf. A000203, A000005.
Sequence in context: A084150 A203196 A192882 * A117133 A083874 A105331
Adjacent sequences: A056073 A056074 A056075 * A056077 A056078 A056079
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KEYWORD
| nonn,changed
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AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 26 2000
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EXTENSIONS
| Corrected by Jason Earls (zevi_35711(AT)yahoo.com), Aug 06 2001
Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 01 2006
a(25)-a(27) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 07 2008
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