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Search: id:A077087
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| A077087 |
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Solutions to Sigma[x+1]=3.Sigma[x]. |
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+0
2
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| 1, 1919, 2759, 11219, 27089, 50039, 58463, 100127, 113831, 115289, 120203, 131879, 148511, 233729, 244319, 308039, 461099, 554063, 596447, 1406303, 1486619, 2285519, 2880989, 5138783, 5369111, 5521619, 5736743, 6621383
(list; graph; listen)
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OFFSET
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1,2
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EXAMPLE
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n=1: sigma[2]/sigma[1]=3/1=3; n=9563231: sigma[n+1]/sigma[n]=31026240/10342080=3
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MATHEMATICA
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Do[s=Mod[a=DivisorSigma[1, n+1], b=DivisorSigma[1, n]]; If[Equal[s, 0]&&Equal[a/b, 3], Print[n]], {n, 1, 10000000}]
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CROSSREFS
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Cf. A000203, A002961, A067081, A077086.
Sequence in context: A069567 A163678 A163863 this_sequence A061374 A157448 A035768
Adjacent sequences: A077084 A077085 A077086 this_sequence A077088 A077089 A077090
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Oct 31 2002
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