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A159953
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Values in A054973 larger than 1.
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2
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2, 2, 3, 2, 2, 3, 3, 2, 2, 3, 5, 2, 3, 3, 4, 2, 2, 2, 2, 4, 2, 2, 2, 2, 2, 5, 2, 2, 6, 4, 2, 2, 5, 2, 5, 3, 3, 3, 7, 3, 6, 2, 3, 2, 2, 6, 3, 2, 4, 2, 3, 8, 2, 9, 4, 2, 6, 2, 2, 2, 2, 2, 2, 4, 8, 4, 2, 2, 2, 3, 4, 3, 9, 2, 10, 2, 3, 2, 4, 4, 3, 4, 2, 2, 11, 5, 2, 5, 2, 3, 4, 2, 2, 3, 5, 3, 8, 7, 4, 15, 2, 4, 7, 8
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OFFSET
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1,1
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COMMENTS
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This is a survey of how many solutions the equation sigma(x)=k has for k in A159886, or about the lengths of the plateaus in A007609.
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LINKS
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MAPLE
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read("transforms3") ; a054973 := BFILETOLIST("b054973.txt") ;
for i from 1 to 1000 do if op(i, a054973) > 1 then printf("%d, ", op(i, a054973)) ; fi; od: # R. J. Mathar, May 22 2009
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MATHEMATICA
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b[n_] := Sum[Boole[DivisorSigma[1, k] == n], {k, 1, n}];
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CROSSREFS
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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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