Sequence to consider

T. D. Noe noe at sspectra.com
Mon Oct 2 18:28:41 CEST 2006


At 10:55 AM -0700 9/30/06, T. D. Noe wrote:
>At 10:19 AM -0700 9/30/06, T. D. Noe wrote:
>>>Smallest odd number A such that sigma(x)=A has n solutions.
>>>
>>>So:  sigma(16)=31 and sigma(25)=31.
>>>
>>
>>I think the sequence begins 1, 31, 347529, 10773399
>>
>>The 3 numbers with sigma(k)=347529 are 164836, 203522, 239121
>>
>>The 4 numbers with sigma(k)=10773399 are 3825936, 4120900, 5088050, 5978025
>
>More terms:
>
>1, 31, 347529, 10773399, 4104665019, 77253471477, 28732655133

I just submitted this sequence as A123523 (Smallest odd number k such that
sigma(x)=k has exactly n solutions).  If anyone has more terms, please
update this sequence.

Tony







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