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A068077
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Numbers n such that sigma(n)+sigma(n+1)=4n.
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2
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OFFSET
| 1,2
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MATHEMATICA
| For[n=1, True, n++, If[DivisorSigma[1, n]+DivisorSigma[1, n+1]==4n, Print[n]]]
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CROSSREFS
| Cf. A067806, A068078.
Sequence in context: A178286 A187938 A172842 * A094427 A138400 A050777
Adjacent sequences: A068074 A068075 A068076 * A068078 A068079 A068080
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KEYWORD
| more,nonn
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AUTHOR
| Dean Hickerson (dean.hickerson(AT)yahoo.com), Feb 16 2002
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EXTENSIONS
| a(6)-a(8) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jan 31 2009
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