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A222174
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Numbers n such that sigma(n) + sigma(n-1) = 3n, where sigma(n) = sum of divisors of n (A000203).
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0
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6, 34, 50, 236, 262, 386, 898, 8362, 26938, 46594, 80876, 5244548, 5462384, 17062316, 323987588, 1162300834, 1381439876
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OFFSET
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1,1
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COMMENTS
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34 is the only number < 10^10 such that sigma(n) + sigma(n+1) = sigma(n) + sigma(n-1) = 3n (34 is a term of A067806).
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LINKS
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MATHEMATICA
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For[n=1, True, n++, If[DivisorSigma[1, n]+DivisorSigma[1, n-1]==3n, Print[n]]]
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PROG
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CROSSREFS
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Cf. A067806 (numbers n such that sigma(n) + sigma(n+1) = 3n), A000203.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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