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A064606
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Partial sum of Sigma_3(n) is divisible by n, where Sigma_3(n)=A001158(n).
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3
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1, 2, 7, 45, 184, 210, 267, 732, 1282, 3487, 98374, 137620, 159597, 645174, 3949726, 7867343, 13215333, 14153570, 14262845, 317186286, 337222295
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Analogous sequences for various arithmetical functions are A050226, A056650, A064605-A064607, A064610, A064611, A048290, A062982, A045345.
a(22) > 2*10^9. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Jun 21 2010]
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FORMULA
| Mod[Sum{sigma_3(j), j=1..n}, n]=Mod[A064603(n), n]=0
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EXAMPLE
| Adding divisor-cube sums for j=1,...,7 gives 1+9+28+73+126+252+344=833=7*119, which is divisible by n=7, so 7 is here and the integer quotient is 119.
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CROSSREFS
| A001158, A064603 A050226, A056650, A064605-A064607, A064610-A064612, A048290, A062982, A045345.
Sequence in context: A006118 A083670 A108240 * A066612 A098637 A162045
Adjacent sequences: A064603 A064604 A064605 * A064607 A064608 A064609
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Sep 24 2001
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EXTENSIONS
| a(15)-a(21) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jun 21 2010
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